The Securities and Exchange Commission has given its final approval to the 2011 XBRL US GAAP Taxonomy as updated by the Financial Accounting Standards Board, giving all public companies a green light to begin or refresh their tag selections for XBRL submissions.

The SEC posted the 2011 GAAP taxonomy to its website with a strong recommendation for companies to use it in submitting their interactive data filings to be sure they're accessing the latest tags. However, SEC staff said companies are allowed to use the 2009 taxonomy since there is not a lot of lead time to transition to the new taxonomy before filings are due in mid-June, especially for the 6,000 public companies who must begin filing in XBRL for the first time this summer.

The SEC approved FASB's taxonomy update with no changes of its own, according to spokesman John Nester. FASB updated the taxonomy to reflect changes in accounting rules since the 2009 release and to reflect holes in the taxonomy that were leading companies to create extensions, or customized tags. With the update, the board also published a 291-page summary of release notes explaining how the taxonomy changed from 2009 to 2011.

The SEC wants to minimize the number of unique extensions companies create to assure greater comparability and utility of the data across all public companies. The staff published guidance in November giving companies plenty of tips on how to improve their XBRL filings, including advice on how to select tags and minimize extensions. FASB also hosted a webcast to explain how companies should use the new taxonomy.

While the largest public companies have fed some six quarters worth of data into the XBRL system so far, the three-year phase-in doesn't bring the smallest companies' data into the system until this summer. During the first phase, large accelerated filers, those with a public float above $5 billion, were required to file in XBRL for periods ending on or after June 15, 2009. The second phase took in all other large accelerated filers for periods ending on or after June 15, 2010.

The final phase applies to all other public companies, including smaller reporting companies and foreign private issuers following international accounting rules. Those companies will be required to file in XBRL for their first fiscal period ending on or after June 15, 2011. While the SEC is studying the filings and working with the data, companies are getting plenty of grace to learn the system before any auditing or regulatory muscle is applied.

Mike Willis, a partner with PwC and founding chair of XBRL International, said companies should begin transitioning from the 2009 to 2011 GAAP Taxonomy if they haven't already done so. Although the SEC hasn't set a mandatory date for transition to the new taxonomy, “it would help companies to conduct an assessment, as the new 2011 taxonomy would help to reduce the level of company-specific extensions for elements that were not included in the 2009 taxonomy,” he says.