Income Taxes - Schedule of Net Operating Losses and Tax Credit Carryforwards (Details) $ in Millions	Dec. 31, 2025 USD ($)
Operating Loss Carryforwards [Line Items]
U.S. foreign tax credit	$ 1,700
United States
Operating Loss Carryforwards [Line Items]
Net operating losses, subject to expire	711
U.S. foreign tax credit	49
U.S. general business credits	66
U.S. corporate alternative minimum tax credits	4
State
Operating Loss Carryforwards [Line Items]
Net operating losses, subject to expire	284
U.K.
Operating Loss Carryforwards [Line Items]
Net operating losses, not subject to expire	286
Bermuda
Operating Loss Carryforwards [Line Items]
Net operating losses, not subject to expire	$ 5,936

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-3

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