XBRL Concept Filter Specification 1.0
Public Working Draft, dated 2006-11-15
Copyright © 2006, XBRL International Inc., All Rights Reserved
This version:
Concept-Filters-PWD-2006-12-18.rtf
is NORMATIVE. All other versions and formats are non-normative.
Editors
Name	Contact	Affiliation	
Phillip Engel	Phillip.Engel@morganstanley.com 	Morgan Stanley	
Geoff Shuetrim	geoff@galexy.net	Galexy	
David vun Kannon	david.k.vunkannon@us.pwc.com 	PricewaterhouseCoopers LLP	
Contributors
Name	Contact	Affiliation	

			
Abstract
This specification is an extension to the XBRL Variables 1.0 Specification Error! Reference source not found..  Specifically, it specifies syntax for a filter that can be used to ensure that a variable only binds to facts for one or more specific concepts.
Status
This is a Public Working Draft whose circulation is unrestricted. Comments should be directed to the editor and/or contributors by e-mail.  Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to provide supporting documentation.
In the final version of this document:
•	relevant schema extracts will be included in the text of the specification
•	relevant examples will be included
•	error codes will be included.
To reduce the editorial burden, these aspects of the specification have been omitted for internal working drafts.
Normative status
This document is normative in the sense that any implementing processor must obey the rules described within it, in order to be considered a conformant processor.
Table of contents
1.1	Document conventions (non-normative)
1.1.1	Typographic conventions
1.1.2	Formatting conventions
1.1.3	Namespace conventions (normative)
1.2	Relationship to other work
1.3	Language independence
1.4	Terminology
1.5	XPath usage
2	Introduction
3	Syntax
3.1	Concept filter declarations
3.1.1	concept-filter relationships
3.1.2	Implied XPath expression
Appendices
A	References (Non Normative)
B	Normative schema
C	Intellectual Property Status (non-normative)
D	Acknowledgements (non-normative)
E	Document History (non-normative)
F	Approval process (non-normative)

1.1	Document conventions (non-normative)
1.1.1	Typographic conventions
Comments which are informative, but not essential to the understanding of the point at hand are provided in footnotes. All footnotes are non-normative.
1.1.2	Formatting conventions
The following highlighting is used to present normative technical material in this document:
	
The following formatting is used for non-normative examples in this document:

The following formatting is used for non-normative counterexamples (examples of poor, discouraged or disallowed usage) in this document:

1.1.3	Namespace conventions (normative)
This table contains all the prefixes used within the text and the correspondent namespace URI. The prefix column in the table above is non normative. The namespace URI column is normative.
Prefix	Namespace URI	
xbrli	http://www.xbrl.org/2003/instance	
xs	http://www.w3.org/2001/XMLSchema	
xfi	http://www.xbrl.org/2005/function/instance	
fn	http://www.w3.org/2006/xpath-functions	
xlink	http://www.w3.org/1999/xlink	
link	http://www.xbrl.org/2003/linkbase	
xl	http://www.xbrl.org/2003/XLink	
generic	http://xbrl.org/2007/generic	
variable	http://xbrl.org/2007/variable	
conceptfilter	http://xbrl.org/2007/conceptFilter	
1.2	Relationship to other work
This specification depends upon XBRL 2.1 Specification [XBRL]. This specification depends upon XBRL Variables 1.0 Specification Error! Reference source not found..
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
All terminology defined in the XBRL 2.1 Specification [XBRL] and the XBRL Variables 1.0 Specification Error! Reference source not found. is used unchanged in this specification.
The following additional terms are used as described in the table below:
Term	Meaning (Normative)	
concept filter	A filter expressed using the concept:filter element.	
concept-filter relationship	A relationship between a concept and a concept filter, expressed by an XLink arc.	
1.5	XPath usage
XPath usage is identical to that in the XBRL Formula 1.0 Specification Error! Reference source not found..
2	Introduction
This specification provides syntax for a filter that can be used to ensure that a variable only binds to facts for a specific concept.
3	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 those explanations are not already provided in other specifications.
3.1	Concept filter declarations
A concept filter is declared by a conceptfilter:concept element in an XBRL extended link.
The syntax for the conceptfilter:concept element is defined by the normative schema supplied with this specification.
The XPath expression implied by a concept filter is determined by relationships between a conceptfilter:concept and concepts declared in XBRL schemas.
3.1.1	concept-filter relationships
Concept filters are associated with concepts by relationships that are expressed using XLink arcs [XLink].
For an XLink arc to define a relationship between a concept and a filter, it MUST:
•	be a generic arc;
•	have an arcrole equal to http://xbrl.org/arcrole/concept-filter
•	have the concept at the source of the arc
•	have the filter at the target of the arc.
Such a relationship is referred to as a concept-filter relationship.
Generic arcs are defined in the Generic Link 1.0 Specification [GENLINK].
3.1.2	Implied XPath expression
The XPath expression implied by a concept filter MUST be constructed as follows.
Begin with the string “true”.
Determine the set of non-prohibited and non-overridden relationships from concepts to the concept filter.
For each such relationship, determine the concept’s namespace, “NAMESPACE”, and the concept’s local name, “LOCALNAME”.  For each NAMESPACE, LOCALNAME pair, append the text:
“ or fn:node-name(.)=fn:QName(’NAMESPACE’,’LOCALNAME’)”
omitting the double quotes.  Note the white space at the beginning of the string to be appended.
The resulting string is the XPath expression implied by the concept filter.
Appendices
A	References (Non Normative)

[GENLINK]	Mark Goodhand (editor)
Generic Links in XBRL, Internal Working Draft
	
[XBRLFunc]	Chris Simmons (editor), Cliff Binstock, Phillip Engel, Herm Fischer, David vun Kannon, Hugh Wallis and Paul Warren
XBRL Functions 1.0 dated 2005-09-23
	
[XBRL]	Phillip Engel, Walter Hamscher, Geoff Shuetrim, David vun Kannon and Hugh Wallis
Extensible Business Reporting Language 2.1 Recommendation with corrected Errata dated 2005-04-25
http://www.xbrl.org/Specification/XBRL-RECOMMENDATION-2003-12-31+Corrected-Errata-2005-04-25.rtf
	
[XLink]	Steve DeRose, Eve Maler, and David Orchard
XML Linking Language (XLink) Version 1.0
http://www.w3.org/TR/xlink
	
B	Normative schema
The following is the normative schema for the concept filter specification.  

<?xml version="1.0" encoding="UTF-8"?>
<schema 
  targetNamespace="http://xbrl.org/2007/conceptFilter"
  xmlns:filter="http://xbrl.org/2007/conceptFilter" 
  xmlns:generic="http://xbrl.org/2007/generic" 
  xmlns:link="http://www.xbrl.org/2003/linkbase" 
  xmlns:xl="http://www.xbrl.org/2003/XLink"
  elementFormDefault="qualified"
  xmlns="http://www.w3.org/2001/XMLSchema" 
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="
  http://www.w3.org/2001/XMLSchema http://www.w3.org/2001/XMLSchema.xsd
  http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd
  ">

  <import namespace="http://www.xbrl.org/2003/XLink" 
    schemaLocation="http://www.xbrl.org/2003/xl-2003-12-31.xsd"/>

  <annotation>
    <appinfo>
      <link:arcroleType
        id="concept-filter" 
        cyclesAllowed="none" 
        arcroleURI="http://xbrl.org/arcrole/concept-filter">
        <link:definition>concept-filter</link:definition>
        <link:usedOn>generic:arc</link:usedOn>
      </link:arcroleType>
    </appinfo>
  </annotation>

  <element name="concept" substitutionGroup="xl:resource">
    <complexType mixed="true">
      <complexContent mixed="true">
        <extension base="xl:resourceType">
          <anyAttribute namespace="http://www.w3.org/XML/1998/namespace" processContents="lax"/>
        </extension>
      </complexContent>
    </complexType>
  </element>

</schema>	
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).
D	Acknowledgements (non-normative)
This document could not have been written without the contributions of many people including the participants in the XBRL Formula Working Group.
E	Document History (non-normative)
Date	Editor	Summary	
2006-12-18	Geoff Shuetrim	First internal working draft created, drawing extensively on the previous Formula specification drafts.	
2007-02-01	Hugh Wallis	Editorial to reflect PWD status