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Income Taxes - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Operating Loss Carryforwards [Line Items] |  |  |  |
Effective income tax rate reconciliation (as a percent) | 23.00% | 23.90% | 23.00% | 23.90%
Effective income tax rate reconciliation, including discrete items (as a percent) | 20.60% | 19.70% | 26.30% | 21.50%
Discrete tax charge (benefit) | $ (7) | $ (7) | $ (14) | $ (9)
Tax charge (benefit) for stock compensation | (8) |  | (8) | (5)
Charge for other small items | 1 | 1 | 2 | 2
Income tax reserve | $ 0 | 0 | $ 20 | 0
Change in deferred tax assets valuation allowance |  |  |  | $ 6
Foreign Tax Authority | Her Majesty's Revenue and Customs (HMRC) |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |
Valuation allowance, deferred tax asset |  | $ 6 |  |

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-12 + Details
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- Definition Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-12 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name Accounting Standards Codification -Section 35 -Paragraph 2 -SubTopic 740 -Topic 718 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480887/718-740-35-2 + Details
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