Q: how do I delete data & documents

     Hope by now you've gotten an answer to your question but if not here are you're two options.  You can either: A.) From your iPhone go to the applications..... SETTINGS➜GENERAL➜USAGE.  Then in the USAGE section you will have the list of your applications show after a brief loading wait.  The number shown on the right of the application names is how much space that app consumes.  Upon clicking it you are shown the specific details of that app and can see the specific amounts of "DOCUMENT AND DATA" usage.  Right under that is the DELETE APP function.  In order for you to erase the accumulated DOCUMENTS AND DATA files you have to actually delete the application, after you go down the list of apps shown on the USAGE page head over to the APP STORE and redownload what you just got done deleting and all of the acumulated DOCUMENTS AND DATA info will be gone.....Or you can go with option B.)  There are a couple iPhone cleaning applications that will go through and delete the acumulation of DOCUMENTS AND DATA files without having to go about the hassle of following option "A".  Yes they cost money and No the free ones wont provide the outcome you want. 

      Im sorry to say, Apple has not come out with any better solution its just onbe of those things.....like you buying a 16g iPhone but it really only having 13.9 available. 

Thank you, i just posted this as a question and found the answer here.