Fair Value Measurements Details of Book Value and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
AFS, at estimated fair value	$ 2,939,594	$ 2,398,352
Debt Securities, Held-to-Maturity, Fair Value	1,033,439	1,072,207
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and due from banks	1,396,282	549,710
FRB and FHLB stock	125,297	124,405
Loans held for sale	26,822	15,158
AFS, at estimated fair value	2,939,594	2,398,352
Debt Securities, Held-to-Maturity, Fair Value	1,244,433	1,267,922
Net Loans	23,730,356	21,057,690
Accrued interest receivable	120,752	107,972
Other financial assets	731,849	661,067
Demand and savings deposits	20,650,955	17,653,690
Brokered deposits	995,975	1,144,692
Time deposits	3,912,724	2,739,241
Accrued interest payable	48,757	35,083
Federal funds purchased		240,000
Federal Home Loan Bank advances	750,000	1,100,000
Senior debt and subordinated debt	535,741	535,384
Other borrowings	892,856	612,142
Other financial liabilities	467,810	429,046
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and due from banks	1,396,282	549,710
FRB and FHLB stock	125,297	124,405
Loans held for sale	26,822	15,158
AFS, at estimated fair value	2,939,594	2,398,352
Debt Securities, Held-to-Maturity, Fair Value	1,033,439	1,072,207
Net Loans	22,391,497	19,930,560
Accrued interest receivable	120,752	107,972
Other financial assets	753,242	661,067
Demand and savings deposits	20,650,955	17,653,690
Brokered deposits	995,975	1,145,379
Time deposits	3,912,608	2,714,709
Accrued interest payable	48,757	35,083
Federal funds purchased		240,000
Federal Home Loan Bank advances	754,414	1,094,013
Senior debt and subordinated debt	419,072	463,270
Other borrowings	892,970	612,106
Other financial liabilities	467,810	429,046
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and due from banks	1,396,282	549,710
FRB and FHLB stock	0	0
Loans held for sale	0	0
AFS, at estimated fair value	0	42,161
Debt Securities, Held-to-Maturity, Fair Value	0	0
Net Loans	0	0
Accrued interest receivable	120,752	107,972
Other financial assets	524,312	452,935
Demand and savings deposits	20,650,955	17,653,690
Brokered deposits	139,166	145,987
Time deposits	0	0
Accrued interest payable	48,757	35,083
Federal funds purchased		240,000
Federal Home Loan Bank advances	754,414	1,094,013
Senior debt and subordinated debt	0	0
Other borrowings	891,851	611,269
Other financial liabilities	173,140	165,635
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and due from banks	0	0
FRB and FHLB stock	125,297	124,405
Loans held for sale	26,822	15,158
AFS, at estimated fair value	2,939,594	2,356,191
Debt Securities, Held-to-Maturity, Fair Value	1,033,439	1,072,207
Net Loans	0	0
Accrued interest receivable	0	0
Other financial assets	175,762	157,540
Demand and savings deposits	0	0
Brokered deposits	856,809	999,392
Time deposits	3,912,608	2,714,709
Accrued interest payable	0	0
Federal funds purchased		0
Federal Home Loan Bank advances	0	0
Senior debt and subordinated debt	419,072	463,270
Other borrowings	1,119	837
Other financial liabilities	280,130	246,157
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and due from banks	0	0
FRB and FHLB stock	0	0
Loans held for sale	0	0
AFS, at estimated fair value	0	0
Debt Securities, Held-to-Maturity, Fair Value	0	0
Net Loans	22,391,497	19,930,560
Accrued interest receivable	0	0
Other financial assets	53,168	50,592
Demand and savings deposits	0	0
Brokered deposits	0	0
Time deposits	0	0
Accrued interest payable	0	0
Federal funds purchased		0
Federal Home Loan Bank advances	0	0
Senior debt and subordinated debt	0	0
Other borrowings	0	0
Other financial liabilities	$ 14,540	$ 17,254