It isn't a choice for any registrant that is filing to the SEC. Even the smallest filers will have to file most reports using XBRL after June.
The application of XBRL doesn't really affect the design of the reports. It ebbs and flows - it feels like more designed filings are coming back with better tools that allow more designed reports.
The is an entire industry that does financial printing; 10k, quarterly reports, prospectuses etc. they handle the filing with SEC/Edgar. If there is a descrepency it arises there. Any one remember when RRDonnelley submitted Googles data a couple hours early during trading and they had to halt trading in the stock?
