How to identify context ID that is presented in Edgar?

Aug 8, 2013 at 7:54 PM
Hi All!
I am new to all XBRL area, so my question may be already answered by I cannot find any references. Any help will be appreciated. So here is the problem. In 10-Q reports stored in SEC edgar system you can find multiple values associated with one xbrl gaap tag. For example ProfitLoss tag will show multiple values. The obvious difference is the context ID. However, in interactive report viewer (ex. http://www.sec.gov/cgi-bin/viewer?action=view&cik=51143&accession_number=0001104659-13-058041&xbrl_type=v#) only some contexts used. How to identify the contexts that used in standard presentation? Apparently they should be encoded in some xml_ext files, but where?

Thank you.
Coordinator
Aug 9, 2013 at 2:56 PM
Hello!

Thanks for your message. I don't have an answer for you right at this moment, but let me do some research and get back to you. I just wanted to let you know that I have received your message so that you didn't think that no one was listening. I'll be in touch soon.

Thanks for trying Gepsio!
Aug 9, 2013 at 3:30 PM
Thank you, Jeffrey.
Just one more bit of information that may help to find an answer. SEC published C# code of their XBRL rendering engine http://www.sec.gov/spotlight/xbrl/renderingenginelicense.htm . It somehow solves the problem of identifying the context ids to show in presentation. I was not able yet to figure out how they did it. Unfortunately, my knowledge of XBRL is too limited yet.

Thank you for Gepsio and for fast reply.
Coordinator
Aug 9, 2013 at 3:33 PM
Let me restate your question to make sure I have it recorded correctly. Please correct me where I am wrong.

An XBRL document defines several contexts. Find the subset of contexts that are actually used in a presentation.

Do I have that right?
Aug 9, 2013 at 3:37 PM
You nailed it. Thanks.
Coordinator
Aug 9, 2013 at 3:46 PM
Thanks for the feedback. I need to add formal support for the presentation linkbase to Gepsio before Gepsio can answer that question, but I can put that on my list to tackle next (I am currently working on adding support for WinRT, Windows Phone 8, and .NET 4.5 into Gepsio). I can imagine one of several implementations, one of which could be the addition of a new Boolean property on Context objects called something like "ReferencedByPresentation":
// WARNING: I'm writing this off the top of my head, so it may be wrong.
foreach(var currentFragment in xbrlDocument)
{
    foreach(var currentContext in currentFragment.Contexts)
    {
        if(currentContext.ReferencedByPresentation == true)
        {
            // context is used in presentation
        }
        else
        {
            // context is not used in presentation
        }
    }
}
Thanks again for trying Gepsio.