The utility of XBRL can be seen in a product just made available by XBRL Cloud which they refer to as GAAP Watch. GAAP Watch is for accountants and no XBRL knowledge is necessary to understand and use it.
The most interesting perspective of GAAP Watch is the "Disclosure" perspective. What it does is allow you to compare different disclosures from different reporting entities.
What is even more interesting is that as SEC XBRL financial filings improve, GAAP Watch will get better and better.
All I can say is watch out Accounting Trends and Techniques. What is REALLY interesting is that you can write your own interface to the information used by GAAP Watch. That is what I did here.
It is looking like accountants are finally starting to get some software which helps them understand that XBRL is potentially useful. There is still a ways to go, but XBRL Cloud's GAAP Watch is a big step in the right direction.
These two videos walk you through the "Entity" and "Disclosure" perspectives of XBRL Cloud's GAAP Watch: