Financial Instruments Subject to Off-Balance Sheet Credit Risk - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Resale agreements
Gross Assets	$ 13,591,000	$ 8,844,000
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0	0
Net Amounts Presented in the Condensed Consolidated Balance Sheets	13,591,000	8,844,000
Counterparty Offsetting	0	0
Collateral	(13,591,000)	(8,844,000)
Net Amount	0	0
Securities borrowed
Gross Assets	1,311,000	1,563,000
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0	0
Net Amounts Presented in the Condensed Consolidated Balance Sheets	1,311,000	1,563,000
Counterparty Offsetting	(1,270,000)	(1,307,000)
Collateral	(40,000)	(253,000)
Net Amount	1,000	3,000
Interest rate swaps
Total Gross Assets	14,903,000	10,407,000
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0	0
Net Amounts Presented in the Condensed Consolidated Balance Sheets	14,903,000	10,407,000
Counterparty Offsetting	(1,270,000)	(1,307,000)
Collateral	(13,631,000)	(9,097,000)
Net Amount	2,000	3,000
Repurchase agreements
Gross Liabilities	8,093,000	4,903,000
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0	0
Net Amounts Presented in the Condensed Consolidated Balance Sheets	8,093,000	4,903,000
Counterparty Offsetting	0	0
Collateral	(8,093,000)	(4,903,000)
Net Amount	0	0
Securities loaned
Gross Liabilities	12,469,000	5,397,000
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0	0
Net Amounts Presented in the Condensed Consolidated Balance Sheets	12,469,000	5,397,000
Counterparty Offsetting	(1,270,000)	(1,307,000)
Collateral	(10,648,000)	(3,619,000)
Net Amount	551,000	471,000
Secured short-term borrowings
Total	10,593,000	6,553,000
Interest rate swaps
Total Gross Liabilities	23,062,000	11,950,000
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0	0
Net Amounts Presented in the Condensed Consolidated Balance Sheets	23,062,000	11,950,000
Counterparty Offsetting	(1,270,000)	(1,307,000)
Collateral	(21,241,000)	(10,172,000)
Net Amount	551,000	471,000
Fair value of client securities available to be pledged	101,320,000	86,911,000
Available for sale securities, assets pledged	90,018,000	107,646,000
Maturity Overnight and on Demand
Securities loaned
Net Amounts Presented in the Condensed Consolidated Balance Sheets	7,500,000
Maturity 30 to 95 Days
Securities loaned
Net Amounts Presented in the Condensed Consolidated Balance Sheets	$ 5,000,000
Minimum
Interest rate swaps
Remaining contractual maturities on securities loaned	30 days
Maximum
Interest rate swaps
Remaining contractual maturities on securities loaned	95 days
Secured short-term borrowings
Secured short-term borrowings
Gross Liabilities	$ 2,500,000	1,650,000
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0	0
Total	2,500,000	1,650,000
Counterparty Offsetting	0	0
Collateral	(2,500,000)	(1,650,000)
Net Amount	0	0
Asset Pledged as Collateral
Interest rate swaps
Available for sale securities, assets pledged	188,000	1,733,000
Interest rate swaps | Asset Pledged as Collateral
Interest rate swaps
Available for sale securities, assets pledged	188,000	195,000
Securities Sold under Agreements to Repurchase
Interest rate swaps
Fair value of collateral pledged in connection with repurchase agreements	8,600,000	5,300,000
Resale and Repurchase Agreements
Interest rate swaps
Fair value of client securities available to be pledged	13,800,000	9,000,000
Interest rate swaps
Interest rate swaps
Gross Assets	1,000	0
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0	0
Net Amounts Presented in the Condensed Consolidated Balance Sheets	1,000	0
Counterparty Offsetting	0	0
Collateral	0	0
Net Amount	1,000	0
Interest rate swaps
Gross Liabilities	0	0
Gross Amounts Offset in the Condensed Consolidated Balance Sheets	0	0
Net Amounts Presented in the Condensed Consolidated Balance Sheets	0	0
Counterparty Offsetting	0	0
Collateral	0	0
Net Amount	0	0
Derivative asset less than stated amount		500
Derivative liability less than stated amount	$ 500	$ 500