Income Taxes (Reconciliation Of Income Tax At Effective Income Tax Rate) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Income tax expense at federal statutory rate	$ (159,343,000)	$ (153,199,000)	$ (209,654,000)
State taxes, net of federal benefit	(20,573,000)	(35,852,000)	(13,029,000)
Differences between statutory rate and foreign effective tax rate	25,178,000	26,271,000	45,810,000
Effective Income Tax Rate Reconciliation, Tax Expense (Benefit), Share-based Payment Arrangement, Amount	(9,204,000)	(7,032,000)	(5,375,000)
Capital loss carryforwards expiration	0	769,706,000	0
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	(3,555,000)	(773,737,000)	(5,813,000)
Effective tax rate reconciliation, accrual for uncertain tax positions	7,365,000	2,637,000	4,923,000
Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions	3,745	436
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	0	(186,800,000)
Transition tax on foreign earnings	0	(5,602,000)	162,353,000
Other	2,867,000	1,725,000	4,397,000
Income tax (expense) benefit	$ 146,477,000	$ 147,027,000	$ 141,764,000