Loans - Summary of Aging of Recorded Investment in Past Due Portfolio Loans by Portfolio Class and Category (Details) - Non-Covered Loans - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Total Past Due	$ 39,117	$ 42,573
Current	7,187,150	7,182,362
Loans, including unearned loan fees	7,226,267	7,224,935
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total Past Due	23,492	21,580
Current	2,907,313	3,067,415
Loans, including unearned loan fees	2,930,805	3,088,995
CRE - investor owned
Financing Receivable, Past Due [Line Items]
Total Past Due	7,765	10,035
Current	1,638,256	1,579,384
Loans, including unearned loan fees	1,646,021	1,589,419
CRE - owner occupied
Financing Receivable, Past Due [Line Items]
Total Past Due	5,222	4,975
Current	1,549,505	1,493,433
Loans, including unearned loan fees	1,554,727	1,498,408
Construction and land development
Financing Receivable, Past Due [Line Items]
Total Past Due	165	13
Current	556,611	546,673
Loans, including unearned loan fees	556,776	546,686
Residential real estate
Financing Receivable, Past Due [Line Items]
Total Past Due	2,386	4,189
Current	303,111	314,990
Loans, including unearned loan fees	305,497	319,179
Other
Financing Receivable, Past Due [Line Items]
Total Past Due	87	1,781
Current	232,354	180,467
Loans, including unearned loan fees	232,441	182,248
Financial Asset, 30 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total Past Due	14,608	13,529
Financial Asset, 30 to 89 Days Past Due [Member] | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total Past Due	8,245	8,652
Financial Asset, 30 to 89 Days Past Due [Member] | CRE - investor owned
Financing Receivable, Past Due [Line Items]
Total Past Due	1,065	734
Financial Asset, 30 to 89 Days Past Due [Member] | CRE - owner occupied
Financing Receivable, Past Due [Line Items]
Total Past Due	4,710	328
Financial Asset, 30 to 89 Days Past Due [Member] | Construction and land development
Financing Receivable, Past Due [Line Items]
Total Past Due	65	13
Financial Asset, 30 to 89 Days Past Due [Member] | Residential real estate
Financing Receivable, Past Due [Line Items]
Total Past Due	461	2,071
Financial Asset, 30 to 89 Days Past Due [Member] | Other
Financing Receivable, Past Due [Line Items]
Total Past Due	62	1,731
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total Past Due	24,509	29,044
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total Past Due	15,247	12,928
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | CRE - investor owned
Financing Receivable, Past Due [Line Items]
Total Past Due	6,700	9,301
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | CRE - owner occupied
Financing Receivable, Past Due [Line Items]
Total Past Due	512	4,647
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Construction and land development
Financing Receivable, Past Due [Line Items]
Total Past Due	100	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential real estate
Financing Receivable, Past Due [Line Items]
Total Past Due	1,925	2,118
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Other
Financing Receivable, Past Due [Line Items]
Total Past Due	$ 25	$ 50