Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Line Items]
U.S. statutory income tax rate	21.00%	35.00%	35.00%
Provisional Tax Act tax expense		$ 773,000,000
Reduction in provisional amount	$ (44,000,000)
Additional tax expense	729,000,000
Unrecognized deferred tax liabilities	0
Increase in valuation allowance balances	7,000,000	37,000,000
Net income impacted due to change in valuation allowances	0	0
Tax loss carryforward, U.S. and non-U.S.	6,000,000
Tax loss carryforward, U.S. and non-U.S., set to expire	0
Cash payments for income taxes	705,000,000	1,800,000,000	$ 1,150,000,000
liabilities for uncertain tax positions	286,000,000	300,000,000	$ 243,000,000	$ 84,000,000
Amount of deferred tax assets possibly to be realized	30,000,000	$ 13,000,000
Maximum
Income Tax Disclosure [Line Items]
Decrease in liabilities for uncertain tax positions	$ 223,000,000