Income Taxes (Balance Sheet Classification) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Assets
Other noncurrent assets	$ 0	$ 393
Liabilities
Noncurrent deferred tax liabilities	186	199
Net deferred tax assets	0	194
Net deferred tax liabilities	$ 186	$ 0

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

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