Schedule II - Valuation and Qualifying Accounts (Details) - Allowance for doubtful accounts - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 2,017	$ 2,121	$ 2,168
Charged to Expenses	828	312	453
Adjustments to Valuation Accounts	0	0	0
Deductions	(695)	(416)	(500)
Balance at End of Period	$ 2,150	$ 2,017	$ 2,121