Where is the SteamVR/ Vive API documentation?

Is there a full SteamVR API documentation? Say I want to know more about the SteamVR_Controller.Input method, as a for instance.

Thanks!

SteamVR API documentation… contains trouble shooting for SteamVR and Vive Pre

https://developer.valvesoftware.com/wiki/SteamVR

The closest thing I know of is the
actual OpenVR API Documentation. The
Unity package is just a C# wrapper for
the C++ dlls. Most of the C++ calls
are available through the C# wrappers,
though some of the latest ones might
not be available in the Unity package
yet.

resource:
https://www.reddit.com/r/SteamVR/comments/5ahayv/steamvr_unity_api_documentation/
documentation is here but it is not very useful for me atm

There is new SteamVR Unity Plugin documentation up on the github here: SteamVR Unity Plugin | SteamVR Unity Plugin