Income Taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2016
Income Tax Disclosure [Line Items]
Provisional tax expense		$ 274,000
2017 Tax Act measurement adjustment	$ 135,700
Income tax expense (benefit), after foreign tax aredits	26,000
Decrease in income tax expense, foreign tax credits	16,000
Transition tax on deemed repatriation	10,100
Alternative minimum tax	9,765	29,700	$ 9,765
Alternative minimum tax expected to be refunded next fiscal year			19,600
Increase (decrease) in deferred tax asset valuation allowance	63,600
Operating loss carryforwards	2,400,000
Deferred tax asset. operating loss carryforward	496,629		495,252
Earnings repatriated	1,200,000
Deferred tax expense, undistributed foreign earnings	60,000
Earnings expected to be repatriated in next fiscal year		1,300,000	100,000
Deferred tax liability, undistributed foreign earnings	5,000	65,000	5,000
Undistributed foreign earnings	1,400,000
Other recorded liabilities for interest and penalties	100	200		$ 100
Income tax expense (benefit) related to interest and penalties	$ (100)	$ (100)		$ (200)
Minimum
Income Tax Disclosure [Line Items]
Expected liability to be added for uncertain taxes during next twelve months			200
Maximum
Income Tax Disclosure [Line Items]
Expected liability to be added for uncertain taxes during next twelve months			$ 1,000