Hi Jim, I think you have a typo regarding his death date.
If you don't know anything about where he was born, etc., the first thing you need is a copy of his obituary. You can request one from Random Acts Genealogical Kindness. Go to http://www.raogk.orghttp://www.raogk.org, read the guidelines, choose Idaho, choose Kootenai Co. and choose one volunteer.
After you receive the obituary, you'll know more about Robert. I found a couple in the Census but didn't know if they were your Robert Thorne or not. Successful Searching & Happy Holidays!