CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Statement of Comprehensive Income [Abstract]
Net income	$ 150	$ 110	$ 397	$ 355
Debt securities available for sale:
Unrealized gains (losses) arising during the period, net of tax expense (benefit) of $3, $21, $18 and $18	13	73	65	62
Derivative instruments:
Unrealized gains (losses) arising during the period, net of tax expense (benefit) of $0, $1, $3 and $(2)	(1)	6	11	(6)
Reclassification adjustment for gains (losses) included in net income, net of tax expense (benefit) of $1, $3, $4 and $7	3	9	15	24
Pension and postretirement benefit obligations:
Unrealized gains (losses) arising during the period, net of tax expense (benefit) of $0, $0, $0 and $0	0	1	1	1
Other Comprehensive Income (Loss)	15	89	92	81
Comprehensive Income (Loss)	$ 165	$ 199	$ 489	$ 436