Schedule II Valuation and Qualifying Accounts and Reserves (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for doubtful accounts
Change in valuation and qualifying accounts and reserves
Balance at Beginning of Period	$ 246,000	$ 207,000	$ 2,375,000
Charged to Costs and Expenses	75,000	58,000	137,000
Deductions	163,000	19,000	2,305,000
Balance at End of Period	158,000	246,000	207,000
Allowance for loan loss
Change in valuation and qualifying accounts and reserves
Balance at Beginning of Period	0	13,670,000	13,897,000
Charged to Costs and Expenses	0	0	0
Deductions	0	13,670,000	227,000
Balance at End of Period	$ 0	$ 0	$ 13,670,000