Fair Value Measurements Carrying Amounts and Estimated Fair Values (Details) - USD ($) $ in Thousands	Dec. 31, 2024		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reported Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
(fair value of $2,156,694 and $2,168,316, respectively)	$ 2,156,694		$ 2,168,316
Cash and due from banks	192,006		202,427
Interest-earning deposits in financial institutions	2,310,206		5,175,149
(amortized cost of $2,526,644 and $2,699,255, respectively)	2,246,839		2,346,864
(fair value of $2,156,694 and $2,168,316, respectively)	2,306,149	[1]	2,287,291
Securities available-for-sale, at fair value	2,246,839
FRB and FHLB stock, at cost	147,773		126,346
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	147,773		126,346
Loans Receivable, Fair Value Disclosure	22,412,073
Warrants and Rights Outstanding			3,689
Equity Securities, FV-NI	3		1
Deposits, Savings Deposits	22,625,485		23,768,896
Time Deposits	4,566,424		6,632,873
Deposits, Fair Value Disclosure	4,556,575		6,732,246
Long-Term Debt	1,391,814		2,911,322
Long-term Debt, Fair Value	1,382,742		2,908,527
Subordinated debt	941,923		936,599
Subordinated Debt Obligations, Fair Value Disclosure	$ 901,532		$ 851,625
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Accrued interest payable and other liabilities		Accrued interest payable and other liabilities
Derivative Liabilities	$ 7,562		$ 6,459
Servicing Rights	19,623		22,174
Debt Securities, Held-to-maturity, Fair Value	2,156,694	[1]	2,168,316
Loans held for sale	26,331		122,757
Loans Held-for-sale, Fair Value Disclosure	26,562		126,646
Interest rate and foreign exchange contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	7,031		8,309
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	192,006		202,427
Interest-earning deposits in financial institutions	2,310,206		5,175,149
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	0		0
Deposits, Savings Deposits	0		0
Deposits, Fair Value Disclosure	0		0
Long-term Debt, Fair Value	0		0
Subordinated Debt Obligations, Fair Value Disclosure	0		0
Loans Held-for-sale, Fair Value Disclosure	0		0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0		0
Interest-earning deposits in financial institutions	0		0
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	147,773		126,346
Deposits, Savings Deposits	22,625,485		23,768,896
Deposits, Fair Value Disclosure	4,556,575		6,732,246
Long-term Debt, Fair Value	1,263,904		2,785,411
Subordinated Debt Obligations, Fair Value Disclosure	901,532		851,625
Loans Held-for-sale, Fair Value Disclosure	26,562		126,646
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0		0
Interest-earning deposits in financial institutions	0		0
Investment in Federal Home Loan Bank Stock, Fair Value Disclosure	0		0
Loans Receivable, Fair Value Disclosure	22,366,111
Warrants Not Settleable in Cash, Fair Value Disclosure	3,763		3,689	$ 4,048	$ 3,555
Deposits, Savings Deposits	0		0
Deposits, Fair Value Disclosure	0		0
Long-term Debt, Fair Value	118,838		123,116
Subordinated Debt Obligations, Fair Value Disclosure	0		0
Loans Held-for-sale, Fair Value Disclosure	0		0
NonPCI and PCI Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Receivable, Fair Value Disclosure			23,551,725
NonPCI and PCI Loans [Member] | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Receivable, Fair Value Disclosure	0		0
NonPCI and PCI Loans [Member] | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Receivable, Fair Value Disclosure	45,962		4,051
NonPCI and PCI Loans [Member] | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans Receivable, Fair Value Disclosure			23,547,674
Fair Value, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
(amortized cost of $2,526,644 and $2,699,255, respectively)	2,246,839
Warrants Not Settleable in Cash, Fair Value Disclosure	3,763		3,689
Cash flow hedges in Cash, Fair Value Disclosure, Liabilities			4,090
Derivative Liability, Fair Value of Collateral	7,562		6,459
Servicing Rights	21,040
Cash flow hedges in Cash, Fair Value Disclosure	1,442
Fair Value, Recurring | Interest rate and foreign exchange contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Asset, Fair Value of Collateral	7,031		8,309
Fair Value, Recurring | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
(amortized cost of $2,526,644 and $2,699,255, respectively)	0		4,968
(fair value of $2,156,694 and $2,168,316, respectively)	173,283		175,579
Equity Securities, FV-NI	3		1
Warrants Not Settleable in Cash, Fair Value Disclosure	0		0
Cash flow hedges in Cash, Fair Value Disclosure, Liabilities			0
Derivative Liability, Fair Value of Collateral	0		0
Servicing Rights	0		0
Cash flow hedges in Cash, Fair Value Disclosure	0
Fair Value, Recurring | Level 1 | Interest rate and foreign exchange contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Asset, Fair Value of Collateral	0		0
Fair Value, Recurring | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
(amortized cost of $2,526,644 and $2,699,255, respectively)	2,244,709		2,301,647
(fair value of $2,156,694 and $2,168,316, respectively)	1,976,265		1,976,015
Equity Securities, FV-NI	0		0
Warrants Not Settleable in Cash, Fair Value Disclosure	0		0
Cash flow hedges in Cash, Fair Value Disclosure, Liabilities			4,090
Derivative Liability, Fair Value of Collateral	7,562		6,459
Servicing Rights	0		0
Cash flow hedges in Cash, Fair Value Disclosure	1,442
Fair Value, Recurring | Level 2 | Interest rate and foreign exchange contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Asset, Fair Value of Collateral	7,031		8,309
Fair Value, Recurring | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
(amortized cost of $2,526,644 and $2,699,255, respectively)	2,130		40,249
(fair value of $2,156,694 and $2,168,316, respectively)	7,146		16,722
Equity Securities, FV-NI	0		0
Warrants Not Settleable in Cash, Fair Value Disclosure	3,763		3,689
Cash flow hedges in Cash, Fair Value Disclosure, Liabilities			0
Derivative Liability, Fair Value of Collateral	0		0
Servicing Rights	21,040		22,174
Cash flow hedges in Cash, Fair Value Disclosure	0
Fair Value, Recurring | Level 3 | Interest rate and foreign exchange contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Asset, Fair Value of Collateral	$ 0		$ 0

[1] Excludes accrued interest receivable of $13.4 million at December 31, 2024 which is recorded in "Other assets" on the consolidated balance shee