Loans - Summary of Aging of Recorded Investment in Past Due Portfolio Loans by Portfolio Class and Category (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financing Receivable, Past Due [Line Items]
Total	$ 10,616,820	$ 9,737,138
Loans, including unearned loan fees	92,931	78,789
Non-Covered Loans
Financing Receivable, Past Due [Line Items]
Total	10,622,397	9,744,427
Loans, including unearned loan fees	10,616,820	9,737,138
Unearned loan fees, net	(5,577)	(7,289)
Loans, before unearned loan fees, after allowance	10,622,397	9,744,427
Non-Covered Loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	4,449,129	3,859,964
Loans, including unearned loan fees	4,449,129	3,859,964
Non-Covered Loans | CRE - investor owned
Financing Receivable, Past Due [Line Items]
Total	2,425,821	2,357,820
Loans, including unearned loan fees	2,425,821	2,357,820
Non-Covered Loans | CRE - owner occupied
Financing Receivable, Past Due [Line Items]
Total	2,361,370	2,270,551
Loans, including unearned loan fees	2,361,370	2,270,551
Non-Covered Loans | Construction and land development
Financing Receivable, Past Due [Line Items]
Total	723,138	611,565
Loans, including unearned loan fees	723,138	611,565
Non-Covered Loans | Residential real estate
Financing Receivable, Past Due [Line Items]
Total	375,986	395,537
Loans, including unearned loan fees	375,986	395,537
Non-Covered Loans | Other
Financing Receivable, Past Due [Line Items]
Total	286,953	248,990
Loans, including unearned loan fees	286,953	248,990
Total Past Due | Non-Covered Loans
Financing Receivable, Past Due [Line Items]
Loans, before unearned loan fees	62,558	15,373
Total Past Due | Non-Covered Loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	23,652	2,928
Total Past Due | Non-Covered Loans | CRE - investor owned
Financing Receivable, Past Due [Line Items]
Total	17,224	1,135
Total Past Due | Non-Covered Loans | CRE - owner occupied
Financing Receivable, Past Due [Line Items]
Total	18,390	8,792
Total Past Due | Non-Covered Loans | Construction and land development
Financing Receivable, Past Due [Line Items]
Total	1,737	1,201
Total Past Due | Non-Covered Loans | Residential real estate
Financing Receivable, Past Due [Line Items]
Total	1,405	1,227
Total Past Due | Non-Covered Loans | Other
Financing Receivable, Past Due [Line Items]
Total	150	90
30-89 Days Past Due | Non-Covered Loans
Financing Receivable, Past Due [Line Items]
Loans, before unearned loan fees	39,640	10,437
30-89 Days Past Due | Non-Covered Loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	15,723	555
30-89 Days Past Due | Non-Covered Loans | CRE - investor owned
Financing Receivable, Past Due [Line Items]
Total	16,287	0
30-89 Days Past Due | Non-Covered Loans | CRE - owner occupied
Financing Receivable, Past Due [Line Items]
Total	5,338	8,628
30-89 Days Past Due | Non-Covered Loans | Construction and land development
Financing Receivable, Past Due [Line Items]
Total	1,737	9
30-89 Days Past Due | Non-Covered Loans | Residential real estate
Financing Receivable, Past Due [Line Items]
Total	446	1,227
30-89 Days Past Due | Non-Covered Loans | Other
Financing Receivable, Past Due [Line Items]
Total	109	18
90 or More Days Past Due | Non-Covered Loans
Financing Receivable, Past Due [Line Items]
Loans, before unearned loan fees	22,918	4,936
90 or More Days Past Due | Non-Covered Loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	7,929	2,373
90 or More Days Past Due | Non-Covered Loans | CRE - investor owned
Financing Receivable, Past Due [Line Items]
Total	937	1,135
90 or More Days Past Due | Non-Covered Loans | CRE - owner occupied
Financing Receivable, Past Due [Line Items]
Total	13,052	164
90 or More Days Past Due | Non-Covered Loans | Construction and land development
Financing Receivable, Past Due [Line Items]
Total	0	1,192
90 or More Days Past Due | Non-Covered Loans | Residential real estate
Financing Receivable, Past Due [Line Items]
Total	959	0
90 or More Days Past Due | Non-Covered Loans | Other
Financing Receivable, Past Due [Line Items]
Total	41	72
Current | Non-Covered Loans
Financing Receivable, Past Due [Line Items]
Loans, before unearned loan fees	10,559,839	9,729,054
Current | Non-Covered Loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	4,425,477	3,857,036
Current | Non-Covered Loans | CRE - investor owned
Financing Receivable, Past Due [Line Items]
Total	2,408,597	2,356,685
Current | Non-Covered Loans | CRE - owner occupied
Financing Receivable, Past Due [Line Items]
Total	2,342,980	2,261,759
Current | Non-Covered Loans | Construction and land development
Financing Receivable, Past Due [Line Items]
Total	721,401	610,364
Current | Non-Covered Loans | Residential real estate
Financing Receivable, Past Due [Line Items]
Total	374,581	394,310
Current | Non-Covered Loans | Other
Financing Receivable, Past Due [Line Items]
Total	$ 286,803	$ 248,900