As previously reported, the 2009 US GAAP Taxonomies are referenced back to the now out of date US GAAP hierarchy. XBRL US, the non-profit nsortium that supports the implementation of XBRL in the United States through the development of taxonomies relevant for use by US public and private sectors, published a Taxonomy Extension that points to the US GAAP dification. But be careful how you choose to use the dification extension.

The official Taxonomies to be used for SEC filings are located on the SEC web If you use a taxonomy that is not listed on the SEC web you risk the EDGAR system being unable to regnize your electronic filing. XBRL US says this in its dification Taxonomy Extension

FAQs:

[The dification taxonomy extension is] “for information purposes and are not regnized as part of the official 2009 taxonomy by the Securities and Exchange mmission (SEC). The dification linkbase file SHOULD NOT be referenced as part of a mpany’s filing as it will not be regnized by the SEC EDGAR system. The dification files can be used by both nsumers of XBRL data and by filers as reference information to understand the origin of individual elements.”

In plain English XBRL US is saying don’t file your 2009 XBRL exhibit with the SEC using the dification taxonomy extension. If you do, the SEC’s Edgar system won’t be able to aept your filing. You should verify that the 2009 US GAAP taxonomy element that most closely matches your financial data is properly tagged to your data. The best practice would also include a separate validation that each tag also agrees with the appropriate level of the Acunting Standard dification (ic, Subic, Section or Paragraph)

The FASB and XBRL US have been working together since 2006. It would have been nice if a smoother XBRL and dification nnection uld have been worked out in advance. It seems that part of the challenge to a smooth transition may have been the SEC’s inability to enable quick integration of new taxonomies into the outdated EDGAR system. Fortunately both issues will be addressed by the 2010 US GAAP Taxonomies, which will be nnected only to the dification. I hope the SEC is planning for more timely integration of new taxonomies into the new IDEA system (under development but partly implemented) that will at first supplement and then replace EDGAR.

The dification taxonomy extension is still useful to investors and the public as they digest XBRL filings after the Acunting Standards dification effective date. However, XBRL software tool users will have to deal with one additional innvenience. When you follow the link to the underlying US GAAP you may be taken to the dification public login page. Anyone can obtain a free login to the basic Acunting Standards dification tool, but it is a bit annoying to have this additional roadblock to seamless operation of XBRL files. Fortunately the 2010 US GAAP taxonomies will also fix this problem.