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
Deduction from asset accounts:
Balance at Beginning of Period	$ 1,850	$ 1,714	$ 1,614
Charged to Expense	282	243	211
Accounts Written Off	(268)	(107)	(111)
Balance at End of Period	$ 1,864	$ 1,850	$ 1,714