Securities - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, allowance for credit loss, excluding accrued interest	$ 0	$ 0	$ 0	$ 0	$ 0
Debt securities, available-for-sale, accrued interest, after allowance for credit loss	8,700,000		8,700,000		9,200,000
Debt securities, available-for-sale, accrued interest writeoff	0	0	0	0
Debt securities, held-to-maturity, allowance for credit loss, excluding accrued interest	0	0	0	0	0
Debt securities, held-to-maturity, accrued interest, after allowance for credit loss	900,000		900,000		900,000
Debt securities, held-to-maturity, accrued interest, writeoff	0	$ 0	0	$ 0
Deposit liabilities, collateral issued, financial instruments	852,100,000		852,100,000		615,700,000
Bank Term Funding Program
Debt Securities, Available-for-sale [Line Items]
Deposit liabilities, collateral issued, financial instruments	0		0		2,400,000,000
Federal Reserve Discount Window
Debt Securities, Available-for-sale [Line Items]
Deposit liabilities, collateral issued, financial instruments	$ 1,900,000,000		$ 1,900,000,000		$ 168,800,000