Segment Information (Reconciliation of Total Segment Income from Operations to Consolidated Income before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting [Abstract]
Income from operations	$ 365,747	$ 46,563	$ 868,161	$ 428,777
Interest expense	(40,036)	(24,366)	(118,784)	(36,966)
Other income (expense), net	2,058	41,265	6,591	52,091
Income before income taxes	$ 327,769	$ 63,462	$ 755,968	$ 443,902