Investment Securities - Narrative (Details) - USD ($)		12 Months Ended
	Jun. 01, 2022	Dec. 31, 2024	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
FRB and FHLB stock, at cost		$ 147,773,000	$ 126,346,000
OCI, Debt Securities, Available-for-Sale, Transfer from Held-to-Maturity, Gain (Loss), before Adjustment and Tax	$ 218,300,000	(157,900,000)
Net Investment Income [Line Items]
OCI, Debt Securities, Available-for-Sale, Transfer from Held-to-Maturity, Gain (Loss), before Adjustment and Tax	(218,300,000)	157,900,000
FRB and FHLB stock, at cost		147,773,000	126,346,000
Debt Securities, Available-for-Sale, Allowance for Credit Loss		0	199,000
Corporate Debt Securities [Member]
Net Investment Income [Line Items]
Debt Securities, Available-for-Sale, Allowance for Credit Loss		0	$ 199,000
Available-for-sale Securities
Investments, Debt and Equity Securities [Abstract]
Available For Sale Securities Pledged As Collateral Amortized Cost		4,200,000
Net Investment Income [Line Items]
Available For Sale Securities Pledged As Collateral Amortized Cost		4,200,000
Held-to-maturity Securities
Net Investment Income [Line Items]
Transfer to Investments	$ 2,300,000,000
Debt Securities, Held-to-Maturity, Restricted		2,200,000,000
Asset Pledged as Collateral
Net Investment Income [Line Items]
Debt Securities, Held-to-Maturity, Restricted		$ 2,100,000,000