Segments and Related Information (Reconciliation of EBITDA to Consolidated Income (Loss) before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
EBITDA Reconciliation:
EBITDA	$ 95,300	$ 53,800	$ 141,500	$ 96,600
Interest expense, net	(12,639)	(12,907)	(24,797)	(23,880)
Depreciation and amortization	(40,657)	(43,254)	(79,664)	(85,852)
Income (loss) before income taxes	$ 42,039	$ (2,376)	$ 37,071	$ (13,116)