Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Doubtful Accounts
Changes in valuation and qualifying accounts
Balance at Beginning of Year	$ 46,425	$ 40,815	$ 41,854
Charged to Cost and Expenses	59,372	44,600	37,423
Deductions	(44,664)	(38,990)	(38,462)
Balance at End of Year	61,133	46,425	40,815
Income Tax Valuation Allowance
Changes in valuation and qualifying accounts
Balance at Beginning of Year	9,641	10,547	13,341
Charged to Cost and Expenses	(2,055)	(906)	(2,794)
Balance at End of Year	$ 7,586	$ 9,641	$ 10,547