SCHEDULE II Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for Doubtful Accounts
Balance at Beginning of Period	$ 695	$ 476	$ 1,655
Charged to (Reduction of) Costs and Expenses	1,321	1,085	250
Taken Against Allowance	(64)	(866)	(1,429)
Other (Deductions) Recoveries	0	0	0
Balance at End of Period	1,952	695	476
Valuation on Allowance for Deferred Tax Assets
Balance at Beginning of Period	6,202	7,691	7,302
Charged to (Reduction of) Costs and Expenses	186	(1,484)	159
Taken Against Allowance	0	0	0
Other (Deductions) Recoveries	0	(5)	230
Balance at End of Period	$ 6,388	$ 6,202	$ 7,691