Schedule II - Valuation and Qualifying Accounts (Details) - Valuation and Qualifying Accounts - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Doubtful Accounts [Member]
Valuation Allowance [Line Items]
Balance at beginning of period	$ 10,368	$ 10,771	$ 16,402
Charged to expenses	7,333	3,886	3,521
Deductions	(3,783)	(4,289)	(9,152)
Balance at end of period	13,918	10,368	10,771
Valuation Allowance of Deferred Tax Assets [Member]
Valuation Allowance [Line Items]
Balance at beginning of period	34,302	63,712	71,912
Adjustments to valuation accounts	(6,397)	(29,410)	(8,200)
Balance at end of period	$ 27,905	$ 34,302	$ 63,712