I mentioned this comparison utility tool in a prior blog post, but it is worth elaborating on a bit more.
This comparison utility tool was created by me in collaboration with Cirrus and XBRL Cloud. I use the XML infosets of an SEC XBRL financial report provided by XBRL Cloud and ideas from Cirrus and wrote an Excel application which generates the comparison that you see below (click on the image to see a bigger image, click here to download the Excel spreasheet):
On the left you see the Costco income statement. On the right you see the Wal Mart income statement. Between the two you see red cells and green cells. The green cells have the row number of the matching report element within the other financial report component being compared. Yellow highlighting indicates no matching report element, white rows indicate that there was a match. Downloading the Excel spreadsheet and looking at it makes it more clear how this works.
The Excel spreadsheet has the income statement and balance sheet comparisons. But, you can compare any two components from any SEC XBRL financial filing. While this is helpful for looking at the primary financial statements, it is even more helpful in analyzing the many disclosures. You can also use this comparison tool to look at changes between the 2012 and 2013 US GAAP Taxonomy.
This comparison is useful because how other reporting entities model a component of a financial report is good information which can be used to be sure you are modeling your financial report appropriately. This is particularly true if the other reporting entity is in your peer group.