Borrowed Funds - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Debt Instrument
Interest payable	$ 45		$ 45	$ 51
FHLB lockout period	12 months		12 months
FHLB available capacity	$ 6,900		$ 6,900	6,600
FHLB advance, maturity period	5 years		5 years
Repayment of FHLB advances upon maturity	$ 1,000	$ 250
Subordinated notes	446		$ 446	444
Decrease in total borrowed funds			1,200
As Initially Reported
Debt Instrument
Junior subordinated debentures	$ 610		$ 610	$ 610