1 Introduction

This document specifies semantics and syntax constraints for abstract relationship axes, implemented by concept relationship and dimensional relationship axes. Relationship axes provide an implementation of predefinedRule axes, as defined in the table specification, based on the use of networks of relationships. They may be in predefined axis subtree hierarchies by use of the composition axis.

2 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 are 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
`table`	`http://xbrl.org/2011/table`
`xbrlte`	`http://xbrl.org/2011/table/error`
`link`	`http://www.xbrl.org/2003/linkbase`
`xbrli`	`http://www.xbrl.org/2003/instance`
`xfi`	`http://www.xbrl.org/2005/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`
`generic`	`http://xbrl.org/2007/generic`

3 Definitions

The figure below provides a model of the relationship axis.

Figure 1: Relationship Axis Model

A relationship axis is an implementation of a predefined axis expressed in terms of concept and dimensional relationship networks.

Axes of concept relationship networks are defined by XBRL 2.1 Base Sets, which are identified by arc role, link role, arc element and link element. Generally at least arc role must be specified (such as the role of parent-child), and a link role or source element, to identify the network of relationships to be considered. Link role, link element name, and arc element name, may be specified as needed.

Axes of dimensional networks are defined by Dimensional Relationship Sets, where the nature of arc is usually unambiguous and determined by the starting concept possibly qualifed with starting link role. These networks follow target role and consecutive arc role as defined for dimensions. To start a network at a primary item that is a source for dimensional relationships, a link role may be required if the primary item participates in multiple networks, but not required where the link role is unique (such as SEC/IFRS filings, where the link role is not known in advance).

The roles and elements are specified by expressions, so that these expressions can refer to parameter and expressions based on bound values, as may be required by accounting schedules.

[Victor Morilla: Every implementation of a predefined axis must be, as they have a defined cardinality (a cardinality that can be computed from the information in the DTS); we can loose this rule by saying that the cardinality can be computed from the information in the DTS and the result of the evaluation of parameters referred in a certain context (let’s not limit ourselves to the context of an instance document). See below ][Herm Fischer: Cardinality, when displaying, also depends on instance data. For example, what dimensions are actually used, what ELRs are actually displayed. See RR example. Sparse displayed columns from a vast ocean of possible dimensional combinations. ]

4 Aspect Covered

A concept relationship axis covers the concept aspect. A dimension relationship aspect covers the dimension aspect. (Whereas the concept aspect, covered by concept relationship axis, applies to all concepts of the DTS (including any dimension concepts), the dimension aspect, covered by a dimension relationship axis, applies only to the specific dimension of at axis.)

5 Relationship Binding

If a relationship axis may has a @name attribute (in the axis or member relationship), then the named binding is to the xfi:relationship.type object which can be referenced in XPath expressions to access values of relationship attributes (such as preferred label or weight).

6 Relationship Source

A relationship axis rule may specify a relationship source concept (by QName expression).

The attribute @includeSource specifies whether the source concept is included in the rendered concepts. If false, the top level rendered concepts are the children of the source concept.

If @includeSource is true (default value): If relationship source is omitted or the constant xfi:root, the root relationships are equivalent to a virtual root source concept that has the root concepts of the network as children. Otherwise (if relationship source is specified and not xfi:root), (a) if the relationship source is neither a concept QName in the DTS of the instance being rendered, nor a source of a relationship, no relationships are found but an error is not raised (this is necessary to deal with financial report filing extension taxonomies that may or not have certain relationships or concepts), or (b) the top level rendered relationship is a virtual relationship that has as its child the named relationship source.

If @includeSource is false: If relationship source is omitted or the constant xfi:root, the root relationships are the relationships whose source is a root concepts of the network, causing the children of these root concepts to be the top level of rendered concepts. Otherwise (if relationship source is specified and not xfi:root), (a) if the relationship source is neither a concept QName in the DTS of the instance being rendered, nor a source of a relationship, no relationships are found but an error is not raised (this is necessary to deal with financial report filing extension taxonomies that may or not have certain relationships or concepts), or (b) the top level rendered relationship is the relationships that have as its parent the named relationship source, causing the children of the relationship source to be the top level of rendered relationships.

7 Syntax

A relationship Axis is represented by a <table:relationshipAxis> aspect rule

A <table:relationshipAxis> element has:

Zero or more <table:relationshipSource> elements, which if present are QName expressions identifying source concept(s) (origins) for ‘tree walking’. The relationshipSource may be omitted, in which case the special QName xfi:root is assumed. QNames that aren’t source concepts for relationship elements in the indicated network are ineffective but not an error.
An optional boolean attribute @includeSource, to indicate that the source element (such as root elements of a financial statement, or the source element of a tree walk, is to be included as a rendered coordinates (otherwise just the to concept (descendants) or from concept (ancestors) is rendered. @includeSource=”true” causes an artificial relationship to appear above the root element, which is a xfi:relationship.type object, established for each such source element, having no arc or link attributes or names.
A <table:linkrole> element which is an expression (xs:string). If none is specified, all link roles are considered.
A <table:arcrole> element which is an expression (xs:string). It is not required on DRS axes types, e.g. “DRS-*”, where the arcrole may be omitted when consecutive relationships are not ambiguous (e.g., when the source is a hypercube, dimension, domain, or member) but not omitted for primary items (when an all, not-all, or primary item inheritance domain-member arcrole must be identified).
A <table:axis> axis type enumeration expression. The axes correspond to xfi:concept-relationships filter axes (descendant, child, ancestor, parent, sibling, or sibling-or-descendant) [xfi:concept-relationships].
An optional <table:generations> expression, whcih is the same as for xfi:concept-relationships (and optional in the same manner).
Optional elements <table:linkName> and <table:arcName> which are expressions (xs:QName), the same as for xfi:concept-relationships. Where not stated, no base set or DRS filtering is performed for link and arc QNames.

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/2011/ - 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/2011/relationship-axis.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.

</restriction>

</simpleType>

</sequence>

</extension>

</complexContent>

</complexType>

</sequence>

</extension>

</complexContent>

</complexType>

</schema>

Appendix B References

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/)
xfi:concept-relationships: "xfi:concept-relationships Function Definition"
Herm Fischer.
(See http://xbrl.org/functionregistry/90507%20xfi.concept-relationships/90507%20xfi.concept-relationships%20function.xml)

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.

Appendix E Document history (non-normative)

Date	Author	Details
12 October 2011	Herm Fischer	Initial draft
03 November 2011	Herm Fischer	Working group updates: replace prior relationshipAxis model with subtrees of compositions and abstract relationshipAxes that have concrete instances of conceptRelationships and dimensionalRelationships. Replace axis-member notion with that of axis subtree composition.
05 December 2011	Herm Fischer	Update class diagram, provide schema definitions.
19 December 2011	Herm Fischer	Editorial updates suggested by Roland Hommes in WG e-mail of 2011-12-08.

Appendix F Errata corrections in this document

This appendix contains a list of the errata corrections that have been incorporated into this document. This represents all those errata corrections that have been approved by the XBRL International Rendering Working Group up to and including 21 December 2011.

No errata have been incorporated into this document.

Relationship Axis 1.0

Public Working Draft 21 December 2011

Status

Abstract

Comments

Table of Contents

Appendices

Table

Figure

Definition