Consolidated Statements of (Loss) Income and Comprehensive (Loss) Income (Parenthetical) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)
Income Statement [Abstract]
Change in net unrealized loss on securities available for sale, tax	$ 8	$ 36	$ 31	$ 15
Change in pension and post-retirement obligations, tax	0	(1)	(1)	(1)
Change in net unrealized gain on cash flow hedges, tax	(13)	(32)	(36)	(9)
Reclassification adjustment for defined benefit plans, tax	0	1	0	0
Reclassification adjustment for net gain on cash flow hedges included in net income, tax	$ 4	$ 1	$ 10	$ 3

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Amount, after adjustment, of tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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