Schedule II-Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Movement in Valuation Allowances and Reserves [Abstract]
Balance at Beginning of Period	$ 14,849	$ 14,769	$ 18,829
Charged to Expense	13,583	15,500	15,532
Accounts Written-off	(14,358)	(15,420)	(19,592)
Balance at End of Period	$ 14,074	$ 14,849	$ 14,769