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Income Taxes - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2024	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Income Tax Contingency [Line Items]
Effective tax rates		18.10%	24.10%	20.90%	21.80%
Tax credit investments		$ 1,875	$ 1,719	$ 1,875	$ 1,719
Internal Revenue Service (IRS)
Income Tax Contingency [Line Items]
Additional estimated federal income tax payment	$ 185
Internal Revenue Service (IRS) \| Penalties
Income Tax Contingency [Line Items]
Additional estimated federal income tax payment	$ 50