Stockholders' Equity Stockholders' Equity (Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 5,238,765	$ 3,581,956
Ending Balance	7,582,157	5,238,765
Foreign Currency
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(19,582)	(20,557)
Other comprehensive income (loss) before reclassifications	(3,939)	975
Net decrease (increase) in accumulated other comprehensive loss	(3,939)	975
Ending Balance	$ (23,521)	$ (19,582)