Derivative and Hedging Activities - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains on derivatives	$ 48,000,000	$ 10,000,000
Interest , loans and leases held-for-sale	30,000,000	24,000,000
Derivative, amount of hedged item	5,900,000,000	6,100,000,000
Unrealized gains	(18,000,000)
Amount of gain (loss), net of tax, to be reclassified during the next 12 months	30,000,000
Derivatives designated as cash flow hedging instruments:
Derivative Instruments, Gain (Loss) [Line Items]
Repayment of FHLB loan advances	2,800,000,000
Amount of gain recognized in accumulated other comprehensive loss	28,200,000
Fair value hedging | Derivatives designated as cash flow hedging instruments:
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	0
Interest rate swaps on FHLB advances | Cash flow hedging | Derivatives designated as cash flow hedging instruments:
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	$ 0	$ 5,500,000,000