Income Taxes - Carryforward (Detail) $ in Millions	Dec. 31, 2019 USD ($)
Federal [Member]
Income Taxes
Capital loss carry-forward	$ 27
State [Member]
Income Taxes
Net operating loss carry-forwards	1,800
Tax credit carry-forward	17
Foreign [Member]
Income Taxes
Tax credit carry-forward	$ 32

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Income Taxes [Line Items]

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