Copyright ©2011 XBRL International Inc., All Rights Reserved.
Circulation of this Recommendation is unrestricted. This document is normative. Recipients are invited to submit comments to formula-feedback@xbrl.org, and to submit notification of any relevant patent rights of which they are aware and provide supporting documentation.
1 Introduction
1.1 Background
1.2 Relationship to other work
1.3 Language independence
1.4 Terminology
1.5 Document conventions (non-normative)
1.6 Namespaces and namespace prefixes
1.7 XPath usage
2 Syntax
2.1 Aspect cover filter
A Normative schema
B References
C Intellectual property status (non-normative)
D Acknowledgements (non-normative)
E Document history (non-normative)
F Errata corrections in this document
1 Namespaces and namespace prefixes
This specification defines XML syntax [XML] for filters that cover aspects that govern implicit filtering and sub-partition of sequences of facts, including:
The filters do not perform any filtering, and thus have no implied XPath expression. (Or for some
implementations that and all the filters of a fact variable together, then
the XPath expression for the filtering action for this
filter would be true() ).
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 instance. It enhances the fact selection capabilities of the XBRL Variables Specification [VARIABLES].
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.
The official language of XBRL International's own work products is English and the preferred spelling convention is UK English.
This specification is consistent with the definitions of any of the terms defined in specifications that it depends on.
Documentation conventions follow those set out in the XBRL Variables Specification [VARIABLES].
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.
| Prefix | Namespace URI |
|---|---|
acf
|
http://xbrl.org/2010/filter/aspect-cover
|
xbrlacfe
|
http://xbrl.org/2010/filter/aspect-cover/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
|
XPath usage is identical to that in the XBRL Variables Specification [VARIABLES].
The XPath expressions implied by
<acf:qnameExpression>
are evaluated using the <xbrli:xbrl> element of the
input XBRL instance
as the context item.
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.
An aspect cover filter is declared by a <acf:aspectCover>
element.
The syntax for the
<acf:aspectCover> element
is defined by the normative schema supplied with this specification.
These filters do not perform any "filtering", and thus have no implied XPath expression. (Or for some
implementations that and all the filters of a fact variable together, then
the XPath expression for the filtering action for this
filter would be true().
These filters declare aspects that would be covered if the arc(s) to the filter
have a @cover attribute that has a value of true, or uncovered
with value false. The following paragraphs describe which aspect(s) would be covered
(or uncovered) under this conditions.
The @complement attribute with a value of true is deemed to have no
effect (no aspect will be covered or uncovered by the action of this filter when complemented).
These filters are processed or applied after other filters (such as concept and dimension) and
'override' the cover state of aspects resulting from the application of the other
filters. For example if some aspect is not covered, this filter overrides to make the aspect covered,
or if covered by other filters, this filter with a @cover attribute of value false would
uncover the indicated aspects.
Error code xbrlacfe:inconsistentAspectCoverFilters
MUST be thrown
if multiple effective aspect cover filters that are associated with a fact variable,
by a variable-filter relationships, provide different (inconsistent) @cover attribute
values for the same aspect.
Future extensions are expected to the standard and will define new aspects. It currently is desired to have xml schema validation of the aspect token, so such extension is likely to require modification of the token list, or relaxation of the schema-based
Because group filters, by definition, do not cover any aspects, an aspect cover group filter has no effect.
Aspects that are to be covered are specified by the
<acf:aspect> and <acf:dimension> child elements of an
<acf:aspectCover> element.
An aspect or dimension element may name an aspect or dimension that does not exist in the current aspect model, or name a dimension aspect that is not present in the dimensions for a candidate fact, which then will be ignored. This allows common aspect cover filters to be reused in different situations.
If the #aspect value is 'all' then all aspects of the candidate fact are deemed
covered. This is equivalent to preventing implicit filtering and preventing sub-partitioning
of sequence results.
If the #aspect value is 'concept', 'entity-identifier', 'location', 'period', 'unit',
'complete-segment', 'complete-scenario', 'non-XDT-segment', or 'non-XDT-scenario'
then that aspect of the candidate fact is covered.
If the #aspect value is 'dimensions' then all the dimension aspects of the candidate
fact are deemed covered. (See <acf:excludeDimension> below, as this provides a way to
cover all but a (or several) specific dimension aspects.)
A dimension may be covered by a <acf:dimension> element. This may either
provide QName specifying the dimension, or by an expression that results
in a QName value representing a dimension. For any <acf:dimension> element,
then the corresponding dimension aspect is specified by the child <acf:qname>
QName constant, or child <acf:qnameExpression> QName value, if such an aspect
exists in the current model. If the QName does not specify a dimension aspect of the fact
being filtered it is ignored.
A dimension may be excluded from covering by this filter, in conjunction to an
#aspect value of 'dimensions' or 'all', by a <acf:excludeDimension> element. This
is important when a formula applies to a large class of instances, some of which extend
known base taxonomies by instance/submission specific extra dimensions, and it is imporant
to prevent implicit filtering and sequence sub-partitioning by the extra extending dimensions.
| Filter1 | Selection criteria2 |
|---|---|
|
<acf:aspectCover>
<acf:aspect> </acf:aspectCover>unit </acf:aspect> |
The unit aspect is covered. This is convenient when fact variables for the same expression have different units (like monetary and shares) and when non-numeric facts (e.g., strings) and numeric facts both exist in the same expression. |
|
<acf:aspectCover>
<acf:dimension> </acf:aspectCover><acf:qname> </acf:dimension>eg:Emperor </acf:qname> |
The aspects to be covered include a dimension concept eg:Emperor,
if that concept represents an XDT dimension in effect for the candidate fact,
and if the dimensional aspect model is in effect.
|
|
<acf:aspectCover>
<acf:aspect> dimensions </acf:aspect><acf:excludeDimension> </acf:aspectCover><acf:qname> </acf:excludeDimension>eg:Emperor </acf:qname> |
An instance may have preparer-unique custom dimensions, which are not desired
to cause implicit filtering or sequence sub-partitioning. The formula author is
only aware of an eg:Emperor dimension, for which the formula author requires normal
uncovered operation. As the author has no control or knowledge of the custom preparer-unique
dimensions, all but eg:Emperor are to be covered. The acf:aspect
for dimensions covers all dimensions and the acf:excludeDimension
excludes eg:Emperor from these otherwise-covered dimension aspects.
|
1. XLink attributes have been omitted.2. Covering is effective if the arc to the filter specifies cover="true".
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:
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/2010/aspect-cover-filter.xsd.
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/aspect-cover-filter.xsd.
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).
This document could not have been written without the contributions of many people including the participants in the Formula Working Group.
| Date | Author | Details |
|---|---|---|
| 28 October 2009 | Herm Fischer |
First internal working draft created, drawing extensively on the previous formula specification drafts. |
| 11 November 2009 | Herm Fischer |
Changes per formula conference call on 2009-11-05, to remove dynamic aspect expression facility.
Removed from core-schemas/aspect-cover-filter.xsd, was between aspect and dimension elements Removed from introduction: "an ability to cover an aspect specified by XPath expression, including future aspects defined by custom aspect models". Removed:
An xs:token value of an evaluated Removed aspectExpression from term definition and examples. |
| 12 December 2009 | Herm Fischer |
Clarified cover and complement attributes per FWG discussions and wiki page. |
| 05 September 2010 | Herm Fischer |
Editorial changes per Hitoshi Okumura. Clarified context item of qnameexpression. Changed schema exceptDimension to excludeDimension to match text. Added error code for inconsistent filters, and statement that aspect cover group filters have no effect. |
| 09 December 2010 | Herm Fischer |
Fixed typo in xbrlacfe:inconsistentAspectCoverFilters per Hitoshi Okumura. |
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 24 October 2011. 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.