Please advise on document editting application that easily syncs (non 3G only) data

I know there are various document editing applications for Ipad. I want a document editor with the following criteria:

• Synchronizes easily (preferably automatically when it detects my home wifi connection) with my PC so I always have another copy of documents worked upon in case of data loss
• Reliable and not prone to crashing
• Is not dependent upon a 3G connection. My IPAD2 is wifi only (and I need to work on documents outside of my house wifi connection) and therefore the apps which integrate with Google Documents, Icloud, or Dropbox are of no use to me

Possibly there is nothing that fits my requirements, but I thought it would not hurt to ask.

Thanks for reading.