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Income Taxes - Narrative (Detail) - USD ($) $ in Millions	12 Months Ended
Income Taxes - Narrative (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating Loss Carryforwards [Line Items]
Operating loss carryforward	$ 46
Credit carryforwards	458	$ 476
Tax credit carryforwards	800
Valuation allowance (decrease) increase	24	(1,030)	$ (98)
Provision for (benefit from) income taxes	313	(723)	74
Deferred tax assets, valuation allowance	220	196
Total unrecognized tax benefit	291	221	$ 159	$ 124
Unrecognized tax benefits that would impact effective tax rate	210
Unrecognized tax benefits, income tax interest and penalties accrued	9	6
Accrued income taxes	68	51
CANADA
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Foreign	150
UNITED KINGDOM
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Foreign	147
Federal
Operating Loss Carryforwards [Line Items]
Credit carryforwards	376
State
Operating Loss Carryforwards [Line Items]
Credit carryforwards	313
Valuation allowance (decrease) increase		(1,050)
Foreign Tax Jurisdiction \| CANADA
Operating Loss Carryforwards [Line Items]
Credit carryforwards	12
California Tax Authority
Operating Loss Carryforwards [Line Items]
Valuation allowance (decrease) increase		20
Deferred tax assets, valuation allowance	$ 220	$ 196