Loans - Recorded Investment in Nonperforming Loans by Category (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	$ 11,079,892	$ 10,884,118
Non-Covered Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual	28,149	43,181
Loans over 90 days past due and still accruing interest	227	547
Total nonperforming loans	28,376	43,728
Loans, including unearned loan fees	11,081,653	10,888,345
Nonaccrual loans with no allowance	5,400	36,078
Non-Covered Loans \| Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	18,295	26,426
Non-Covered Loans \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	482	5,202
Non-Covered Loans \| Blanket Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	736	2,175
Non-Covered Loans \| Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	3,733	3,445
Non-Covered Loans \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual	6,648	7,641
Loans over 90 days past due and still accruing interest	227	115
Total nonperforming loans	6,875	7,756
Loans, including unearned loan fees	4,631,613	4,674,056
Nonaccrual loans with no allowance	296	6,179
Non-Covered Loans \| Commercial and industrial \| Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	296	527
Non-Covered Loans \| Commercial and industrial \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	0	1,864
Non-Covered Loans \| Commercial and industrial \| Blanket Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	0	344
Non-Covered Loans \| Commercial and industrial \| Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	3,733	3,445
Non-Covered Loans \| Commercial - investor owned
Financing Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual	14,284	20,404
Loans over 90 days past due and still accruing interest	0	0
Total nonperforming loans	14,284	20,404
Loans, including unearned loan fees	2,526,696	2,452,402
Nonaccrual loans with no allowance	0	19,466
Non-Covered Loans \| Commercial - investor owned \| Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	14,284	19,467
Non-Covered Loans \| Commercial - investor owned \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	0	0
Non-Covered Loans \| Commercial - investor owned \| Blanket Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	0	0
Non-Covered Loans \| Commercial - investor owned \| Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	0	0
Non-Covered Loans \| Commercial - owner occupied
Financing Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual	6,432	12,972
Loans over 90 days past due and still accruing interest	0	363
Total nonperforming loans	6,432	13,335
Loans, including unearned loan fees	2,381,636	2,344,117
Nonaccrual loans with no allowance	4,577	9,010
Non-Covered Loans \| Commercial - owner occupied \| Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	3,715	5,904
Non-Covered Loans \| Commercial - owner occupied \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	482	1,638
Non-Covered Loans \| Commercial - owner occupied \| Blanket Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	736	1,831
Non-Covered Loans \| Commercial - owner occupied \| Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees	0	0
Non-Covered Loans \| Construction and land development
Financing Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual	527	1,205
Loans over 90 days past due and still accruing interest	0	64
Total nonperforming loans	527	1,269
Loans, including unearned loan fees	896,768	760,122
Nonaccrual loans with no allowance	527	464
Non-Covered Loans \| Construction and land development \| Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees		528
Non-Covered Loans \| Construction and land development \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees		741
Non-Covered Loans \| Construction and land development \| Blanket Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees		0
Non-Covered Loans \| Construction and land development \| Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees		0
Non-Covered Loans \| Residential
Financing Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual	258	959
Loans over 90 days past due and still accruing interest	0	0
Total nonperforming loans	258	959
Loans, including unearned loan fees	354,888	371,995
Nonaccrual loans with no allowance	0	959
Non-Covered Loans \| Residential \| Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees		0
Non-Covered Loans \| Residential \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees		959
Non-Covered Loans \| Residential \| Blanket Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees		0
Non-Covered Loans \| Residential \| Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, including unearned loan fees		0
Non-Covered Loans \| Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Nonaccrual		0
Loans over 90 days past due and still accruing interest		5
Total nonperforming loans		5
Loans, including unearned loan fees	$ 290,052	285,653
Nonaccrual loans with no allowance		$ 0

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Amortized cost excluding accrued interest, of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

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