Borrowings - FHLB and FRB Advances (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
FHLB and FRB advances	$ 1,203,207	$ 500,000
FHLB advances, interest rate	3.91%	3.37%
Amount
2024	$ 250,000
2025	200,000
2026	200,000
2027	450,000
2028	100,000
Thereafter	0
Total long-term FHLB advances	$ 1,200,000
Rate
2024	3.44%
2025	4.45%
2026	4.32%
2027	3.70%
2028	4.19%
Thereafter	0.00%
Total maximum borrowing capacity with the FHLB	$ 3,474,347	$ 3,241,120
Total maximum borrowing capacity with the FRB	3,436,000	2,510,189
Loans and leases receivable	11,889,120	13,144,894
FHLB advances
Rate
Cumulative Amount of Fair Value Hedging Adjustment to Hedged Items	3,200
FHLB Advance Due June 2024
Debt Instrument [Line Items]
FHLB and FRB advances	250,000
FHLB Advance Due June 2027
Debt Instrument [Line Items]
FHLB and FRB advances	950,000
Bank Term Funding Program
Rate
Aggregate availability under federal funds line	475,300
Qualifying Assets Pledged as Collateral
Rate
Loans and leases receivable	$ 8,575,137	$ 7,142,865

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