Income Taxes (Provision For Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal, Current			$ 239,566	$ 102,786	$ (71,878)
State, Current			40,788	2,760	(7,304)
Current Foreign Tax Expense (Benefit)			(10,080)	19,597	0
Federal, Deferred			46,434	(156,767)	100,208
State, Deferred			27,845	28,527	(1,615)
Deferred Foreign Income Tax Expense (Benefit)	$ 6,600	$ 1,400	2,690	(9,282)	0
Income tax provision total			$ 347,243	$ (12,379)	$ 19,411