Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Comprehensive Income [Abstract]
Net unrealized gains (losses) on securities available for sale, tax	$ (459)	$ (222)	$ 1,415
Net unrealized gains (losses) on derivative instruments, tax	(104)	(114)	382
Net pension and postretirement benefit costs, tax	$ 8	$ 0	$ 1

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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