Income Taxes - Deferred Tax Asset Valuation Allowances (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Valuation Allowance [Line Items]
Other amortizable assets	$ 394	$ 49
Valuation Allowance	(330)	$ (138)
Other amortizable assets
Valuation Allowance [Line Items]
Other amortizable assets	394
Valuation Allowance	(243)
Tax credits
Valuation Allowance [Line Items]
Tax credits	387
Valuation Allowance	(29)
NOLs - Non-U.S.
Valuation Allowance [Line Items]
NOLs - Non-U.S.	33
Valuation Allowance	(18)
Other carryforwards
Valuation Allowance [Line Items]
Other carryforwards	27
Valuation Allowance	(27)
NOLs - State
Valuation Allowance [Line Items]
NOLs - State	13
Valuation Allowance	$ (13)

Deferred Tax Assets, Other Amortizable Assets

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign operating loss carryforwards.

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