Borrowings - FHLB and FRB Advances (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
FHLB advances	$ 2,050,000
Amount
2024	420,000
2025	540,000
2026	540,000
2027	450,000
Thereafter	100,000
FHLB advances	$ 2,050,000
Rate
2024	4.26%
2025	5.21%
2026	5.23%
2027	3.70%
Thereafter	0.0419
Total maximum borrowing capacity with the FHLB	$ 3,307,772	$ 3,241,120
Total maximum borrowing capacity with the FRB	6,516,922	2,510,189
Loans and leases receivable	13,145,352	13,144,894
FHLB advances
Debt Instrument [Line Items]
Total long-term debt	$ 2,052,143	$ 500,000
FHLB advances, rate	4.64%	3.37%
Rate
Cumulative Amount of Fair Value Hedging Adjustment to Hedged Items	$ 2,100
FHLB Advance Due September 2026
Debt Instrument [Line Items]
FHLB advances	1,100,000
Amount
FHLB advances	1,100,000
FHLB Advance Due March 2028
Debt Instrument [Line Items]
FHLB advances	950,000
Amount
FHLB advances	$ 950,000
FHLB Advance Due June 2027
Debt Instrument [Line Items]
FHLB advances, interest rate	3.30%
FHLB advances	$ 250,000
Amount
FHLB advances	250,000
Bank Term Funding Program
Rate
Borrowing capacity available under the BTFP	508,200
Qualifying Assets Pledged As Collateral
Rate
Loans and leases receivable	$ 12,079,694	$ 7,142,865

Federal Home Loan Bank, Advance, Maturity, after Year Four

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Federal reserve bank maximum amount available.

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