If you believe that XBRL provides benefits only to consumers of business information and the the creators of business information gain nothing from its use, think again. One way to see the benefits of XBRL to users is to look at business rules. A good source of information about business rules is the Business Rules Group, particularly their Business Rules Manifesto.
Business rules are commonly defined as:
A formal and implementable expression of some user requirement.
Business rules are implemented in XBRL using XBRL Formulas. XBRL Formulas became a recommendation just a few weeks ago, but has been around and on the minds of the creators of XBRL from its inception.
If you don't understand what business rules are, you cannot possibly understand XBRL or its true value to both creators and consumers of business information. Business rules benefit business information which is expressed and the processes used to express business information.
While the XBRL taxonomies such as the IFRS and US GAAP do not provide business rules with the taxonomies today, you will definitely see them in the future.
If you don't understand business rules, a good place to start is by reading that Business Rules Manifesto. It will give you a good sense for what business rules are and what benefits they provide.