Income Taxes - Schedule of Operating Loss and Tax Credit Carryforwards (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Tax Credit Carryforward [Line Items]
Federal loss carryforwards	$ 38	$ 44
State loss carryforwards	2	$ 9
Domestic Tax Authority \| Expiring 2026-2035
Tax Credit Carryforward [Line Items]
Federal loss carryforwards	38
State and Local Jurisdiction \| Expiring 2027-2040
Tax Credit Carryforward [Line Items]
State loss carryforwards	$ 2

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32632-109319

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32621-109319

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

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