1 Introduction

This specification is an extension to [VARIABLES]. It defines XML [XML] syntax for and-filters that combine sub-filters so that facts are required to satisfy all of them and or-filters that combine sub-filters so that facts are required to satisfy any one of them.

A sub-filter is any filter that is related to a Boolean filter by a Boolean-filter relationship.

All filters defined in this specification are referred to as Boolean filters.

1.1 Background

This specification is a member of a suite of similar specifications that define specific types of criteria that can be used to select facts from input XBRL instances. It enhances the fact selection capabilities of the XBRL Variables Specification [VARIABLES].

1.2 Relationship to other work

This specification depends upon the XBRL Specification [XBRL 2.1], and the XBRL Variables Specification [VARIABLES]. In the event of any conflicts between this specification and the specifications upon which it depends, this specification does not prevail.

1.3 Language independence

The official language of XBRL International's own work products is English and the preferred spelling convention is UK English.

1.4 Terminology

This specification is consistent with the definitions of any of the terms defined in specifications that it depends on.

1.5 Document conventions (non-normative)

Documentation conventions follow those set out in the XBRL Variables Specification [VARIABLES].

1.6 Namespaces and namespace prefixes

Namespace prefixes [XML NAMES] will be used for elements and attributes in the form ns:name where ns is the namespace prefix and name is the local name. Throughout this specification, the mappings from namespace prefixes to actual namespaces is consistent with Table 1.

The prefix column in Table 1 is non normative. The namespace URI column is normative.

Table 1: Namespaces and namespace prefixes

Prefix	Namespace URI
`bf`	`http://xbrl.org/2008/filter/boolean`
`xbrlbfe`	`http://xbrl.org/2008/filter/boolean/error`
`eg`	`http://example.com/`
`fn`	`http://www.w3.org/2005/xpath-functions`
`link`	`http://www.xbrl.org/2003/linkbase`
`xbrli`	`http://www.xbrl.org/2003/instance`
`xfi`	`http://www.xbrl.org/2008/function/instance`
`xbrldi`	`http://xbrl.org/2006/xbrldi`
`xbrldt`	`http://xbrl.org/2005/xbrldt`
`xl`	`http://www.xbrl.org/2003/XLink`
`xlink`	`http://www.w3.org/1999/xlink`
`xs`	`http://www.w3.org/2001/XMLSchema`
`xsi`	`http://www.w3.org/2001/XMLSchema-instance`
`gen`	`http://xbrl.org/2008/generic`
`variable`	`http://xbrl.org/2008/variable`
`iso4217`	`http://www.xbrl.org/2003/iso4217`

1.7 XPath usage

XPath usage is identical to that in the XBRL Variables Specification [VARIABLES].

2 Syntax

This specification only provides a textual declaration of syntax constraints when those constraints are not expressed by the normative schema supplied with this specification.

Explanations of elements and attributes are only supplied when explanations are not already provided in other specifications.

Unless explicitly stated otherwise, a reference to a specific element MUST be read as a reference to that element or to any element in its substitution group.

2.1 And-filter

An and-filter is declared by a <bf:andFilter> element.

The syntax for the <bf:andFilter> element is defined by the normative schema supplied with this specification.

The and-filter can be used to match facts based upon criteria expressed by each one of its sub-filters.

The XPath expression implied by an and-filter contains one term for each of its sub-filters or sub-filter complements. The term for each sub-filter or sub-filter complement is the XPath expression implied by that sub-filter or sub-filter complement. The terms are combined to form a single XPath and-expression by separating them with the and token.

An and-filter can cover all of the aspects that are covered by its sub-filters.

Example 1: And filters

Sub filters	Implied constraint
Concept name filter matching facts with concepts that are named `<eg:assets>` Specific entity scheme filter matching facts with an entity identifier in the scheme `http://www.example.com/entity/identification`	Facts matching the and-filter must be named `<eg:assets>` and have a context with an entity identifier that is in the `http://www.example.com/entity/identification` scheme
Parent filter matching facts with the parent `<xbrli:xbrl>` Forever filter matching facts that are reported with a "forever" context period	Facts must not be contained by a tuple and they must be reported with a period of "forever".

2.2 Or-filter

An or-filter is declared by a <bf:orFilter> element.

The syntax for the <bf:orFilter> element is defined by the normative schema supplied with this specification.

The or-filter matches facts based upon criteria expressed by any one of its sub-filters.

The XPath expression implied by an or-filter contains one term for each of its sub-filters or sub-filter complements. The term for each sub-filter or sub-filter complement is the XPath expression implied by that sub-filter or sub-filter complement. The terms are combined to form a single XPath or-expression by separating them with the or token.

An or-filter can cover all of the aspects that are covered by its sub-filters.

Example 2: Or filters

Sub filters	Implied constraint
Concept name filter matching facts with concepts that are named `<eg:assets>` Concept name filter matching facts with concepts that are named `<eg:totalAssets>`	Facts must be named either `<eg:assets>` or `<eg:totalAssets>`

2.3 Boolean-filter relationships

A Boolean-filter relationship is a relationship between a Boolean filter and a sub-filter expressed by an XLink arc.

To declare a Boolean-filter relationship an XLink arc MUST:

have an arcrole value equal to http://xbrl.org/arcrole/2008/boolean-filter
have the Boolean filter at the starting resource of the arc
have the sub-filter at the ending resource of the arc

The arcrole value, http://xbrl.org/arcrole/2008/boolean-filter, is declared in the normative schema for Boolean filters.

Boolean-filter relationships MUST be expressed by variable-filter arcs. Violations of this requirement can be detected by validation against the XBRL Specification [XBRL 2.1].

A complemented Boolean-filter relationship is a Boolean-filter relationship that is expressed by an arc with a @complement attribute that has a value of true.

A Boolean filter with a complemented Boolean-filter relationship to a sub-filter uses the filter complement of the sub-filter in its implied XPath expression rather than the filter itself.

A covering Boolean-filter relationship is a Boolean-filter relationship that is expressed by an arc with a @cover attribute that has a value of true.

If a sub-filter is related to a Boolean filter by a Boolean-filter relationship, that filter only covers aspects of the facts being filtered if the Boolean-filter relationship is a covering Boolean-filter relationship.

Appendix A Normative schema

The following is the XML schema provided as part of this specification. This is normative. Non-normative versions (which should be identical to these except for appropriate comments indicating their non-normative status) are also provided as separate files for convenience of users of the specification.

NOTE: (non-normative) Following the schema maintenance policy of XBRL International, it is the intent (but is not guaranteed) that the location of non-normative versions of these schemas on the web will be as follows:

While any schema is the most current RECOMMENDED version and until it is superseded by any additional errata corrections a non-normative version will reside on the web in the directory http://www.xbrl.org/2008/ - during the drafting process for this specification this directory should contain a copy of the most recent published version of the schema at http://www.xbrl.org/2008/boolean-filter.xsd.
A non-normative version of each schema as corrected by any update to the RECOMMENDATION will be archived in perpetuity on the web in a directory that will contain a unique identification indicating the date of the update.

<link:definition>

boolean-filter has sub-filter

</link:definition>

<link:usedOn>

variable:variableFilterArc

</link:usedOn>

</link:arcroleType>

</appinfo>

</annotation>

</schema>

Appendix B References

CONCEPT FILTERS: XBRL International Inc.. "XBRL Concept Filters 1.0"
Phillip Engel, Herm Fischer, Victor Morilla, Jim Richards, Geoff Shuetrim, David vun Kannon, and Hugh Wallis.
(See ../../conceptFilters/REC-2009-06-22/conceptFilters-REC-2009-06-22.html)
ENTITY FILTERS: XBRL International Inc.. "XBRL Entity Filters 1.0"
Phillip Engel, Herm Fischer, Victor Morilla, Jim Richards, Geoff Shuetrim, David vun Kannon, and Hugh Wallis.
(See ../../entityFilters/CR-2008-12-31/entityFilters-CR-2008-12-31.html)
PERIOD FILTERS: XBRL International Inc.. "XBRL Period Filters 1.0"
Phillip Engel, Herm Fischer, Victor Morilla, Jim Richards, Geoff Shuetrim, David vun Kannon, and Hugh Wallis.
(See ../../periodFilters/REC-2009-06-22/periodFilters-REC-2009-06-22.html)
TUPLE FILTERS: XBRL International Inc.. "XBRL Tuple Filters 1.0"
Phillip Engel, Herm Fischer, Victor Morilla, Jim Richards, Geoff Shuetrim, David vun Kannon, and Hugh Wallis.
(See ../../tupleFilters/REC-2009-06-22/tupleFilters-REC-2009-06-22.html)
VARIABLES: XBRL International Inc.. "XBRL Variables 1.0"
Phillip Engel, Herm Fischer, Victor Morilla, Jim Richards, Geoff Shuetrim, David vun Kannon, and Hugh Wallis.
(See ../../variables/REC-2009-06-22/variables-REC-2009-06-22.html)
XBRL 2.1: XBRL International Inc.. "Extensible Business Reporting Language (XBRL) 2.1"
Phillip Engel, Walter Hamscher, Geoff Shuetrim, David vun Kannon, and Hugh Wallis.
(See http://www.xbrl.org/Specification/XBRL-RECOMMENDATION-2003-12-31+Corrected-Errata-2008-07-02.htm)
XLINK: W3C (World Wide Web Consortium). "XML Linking Language (XLink) Version 1.0"
Steve DeRose, Eve Maler, and David Orchard.
(See http://www.w3.org/TR/xlink/)
XML: W3C (World Wide Web Consortium). "Extensible Markup Language (XML) 1.0 (Fourth Edition)"
Tim Bray, Jean Paoli, C. M. Sperberg-McQueen, Eve Maler, and François Yergeau.
(See http://www.w3.org/TR/REC-xml/)
XML NAMES: W3C (World Wide Web Consortium). "Namespaces in XML 1.0 (Second Edition)"
Tim Bray, Dave Hollander, Andrew Layman, and Richard Tobin.
(See http://www.w3.org/TR/REC-xml-names/)
XML SCHEMA STRUCTURES: W3C (World Wide Web Consortium). "XML Schema Part 1: Structures Second Edition"
Henry S. Thompson, David Beech, Murray Maloney, and Noah Mendelsohn.
(See http://www.w3.org/TR/xmlschema-1/)
XPATH 2.0: W3C (World Wide Web Consortium). "XML Path Language (XPath) 2.0"
Anders Berglund, Scott Boag, Don Chamberlin, Mary F. Fernández, Michael Kay, Jonathan Robie, and Jérôme Siméon.
(See http://www.w3.org/TR/xpath20/)

Appendix C Intellectual property status (non-normative)

This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to XBRL International or XBRL organizations, except as required to translate it into languages other than English. Members of XBRL International agree to grant certain licenses under the XBRL International Intellectual Property Policy (www.xbrl.org/legal).

This document and the information contained herein is provided on an "AS IS" basis and XBRL INTERNATIONAL DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

The attention of users of this document is directed to the possibility that compliance with or adoption of XBRL International specifications may require use of an invention covered by patent rights. XBRL International shall not be responsible for identifying patents for which a license may be required by any XBRL International specification, or for conducting legal inquiries into the legal validity or scope of those patents that are brought to its attention. XBRL International specifications are prospective and advisory only. Prospective users are responsible for protecting themselves against liability for infringement of patents. XBRL International takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Members of XBRL International agree to grant certain licenses under the XBRL International Intellectual Property Policy (www.xbrl.org/legal).

Appendix D Acknowledgements (non-normative)

This document could not have been written without the contributions of many people including the participants in the Formula Working Group.

Appendix E Document history (non-normative)

Date	Author	Details
14 November 2007	Geoff Shuetrim	First internal working draft created. This is intended to simplify all of the filters where internal structures have been trying to duplicate Boolean functionality on a piecemeal basis.
15 November 2007	Geoff Shuetrim	Added a `@complement` attribute to boolean-filter relationships to capture the same functionality provided by the attribute on variable-filter relationships. This enables Boolean filters to combine filters with filter complements instead of only combining filters. Added a `@cover` attribute to boolean-filter relationships to capture the same functionality provided by the attribute on variable-filter relationships.
16 November 2007	Geoff Shuetrim	At the suggestion of Victor Morilla removed the paragraph saying that or-filters cover no aspects. A use case supporting this removal is the combination of a set of concept-name filters with an or-filter. This would not naturally warrant not covering the concept aspect. If users do not wish an or-filter to cover aspects, then the users are able to use the cover attribute to achieve this outcome.
24 November 2007	Geoff Shuetrim	Clarified the wording of the introduction to make it more specific about the features being made available.
26 November 2007	Geoff Shuetrim	Added examples.
29 November 2007	Geoff Shuetrim	Clarified what aspects can be covered by Boolean filters.
01 December 2007	Geoff Shuetrim	Fixed typographic error found by Herm Fischer in the or-filter examples.
20 January 2008	Geoff Shuetrim	Fixed obsolete reference in the normative schema and in the text of the specification to the `<variable:arc>`, instead using the `<variable:variableFilterArc>` arc as defined on 26 November, 2007 in the Variables specification [VARIABLES].
31 January 2008	Geoff Shuetrim	Standardised the format of the hyperlinks to the normative schema.
13 August 2008	Geoff Shuetrim	Removed un-necessary schema limitations on undirected cycles in relationship networks.
15 December 2008	Geoff Shuetrim	Fixed formatting issues and clarified a reference to covering Boolean-filter relationships. Updated references to the latest errata-corrected version of the XBRL 2.1 specification.

Appendix F Errata corrections in this document

This appendix contains a list of the errata that have been incorporated into this document. This represents all those errata corrections that have been approved by the XBRL International Formula Working Group up to and including 22 June 2009. Hyperlinks to relevant e-mail threads may only be followed by those who have access to the relevant mailing lists. Access to internal XBRL mailing lists is restricted to members of XBRL International Inc.

No errata have been incorporated into this document.

Boolean Filters 1.0

Recommendation 22 June 2009

Status

Abstract

Table of Contents

Appendices

Table

Examples

Definitions