Do you have the documents backed up? I think it is best to move documents outside of the apple ecosystem to ensure you have a copy. If the documents are not backed up, it going to cost you.
I suggest you use dropbox.com or box.com for backing up.
How to recover data.
1) Stop using the device.
2) Take it to a professional.
http://www.drivesaversdatarecovery.com/devices-supported/apple-ipad-data-recover y/
Things you can try.
Use iExplorer on a backup. See if you can fish out the files.
https://www.macroplant.com/iexplorer/
Stop using your iDevice immediately. Try on of these applications on your computer.
Easy-to-Use iPhone Data Recovery
Accidentally delete important iPhone files? Hardware or system Malfunction? iPhone Data Recovery is specially designed to help you recover deleted photos, videos, messages, contacts, call history, notes, etc. from iPhone directly or extract backup files from iTunes & iCloud to restore deleted files, so that you can save them on your computer or Mac with one easy click.
http://www.fonepaw.com/iphone-data-recovery/
Dr.Fone for iOS (iPad/iPhone/iPod Data Recovery) "Get Back Your Lost Contacts, Photos, Messages and More Freaking out cause you accidentally deleted photos, text messages or other crucial stuff on your iPhone, iPad or iPod? Broke or damaged your iPhone or iPod and now the data's gone? Failed updates kill your data? The bottom line is, whatever the problem, the doctor is in! iPad/iPhone/iPod Recovery is an easy-to-use tool that can help you easily recover photos & videos, contacts, SMS, call logs, memos and calendars, even Safari bookmarks you thought you'd lost forever! How does it work? Just follow a few simple steps and, you can preview your lost files, recover in a snap and you are back - like that. Currently, you can recover up to 12 file types from all iOS devices. For file types that are able to recover directly from iOS device, please check the table below." http://software.bigbigsoft.com/ipod-ipad-iphone-recovery
