I have read on the poor mans patent, but I am wondering if there is any legal backing for a idea that was written in a document and stored on a local file system. I do realize that this is faulty because the date and what not can be forged on the local file system, but does it merit any sort of legal backing. Are provisionals filed through USPTO the only ones that are recognized?
I am wondering if there is any legal backing for a idea that was written in a document and stored on a local file system
No, especially now that the US is in a first-inventor-to-file regime. Documenting that you conceived of it first did have relevance pre the AIA patent law in 2012. Who was first to conceive is no longer relevant.
The only way your own documentation of your inventive progress can help you is if you told someone about it under a condition of confidentially and they filed, stealing your invention. You could try to use whatever evidence you had to show that they derived it from you.
Are provisionals filed through USPTO the only ones that are recognized?
In a word, yes. As George White said in his answer, the US and pretty much the rest of the world works on a first to file system. To gain patent protection, you must first file an application with a patent authority. In the US, that is the USPTO.