Schedule II-Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Doubtful Accounts
Beginning Balance	$ 10,662	$ 7,640	$ 7,617
Additions Charged To Expense	8,047	9,347	7,787
Deductions From Reserve	(7,108)	(6,325)	(7,763)
Ending Balance	$ 11,601	$ 10,662	$ 7,640