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Loans and Allowance for Credit Losses on Loans HFI - Schedule of Loans Outstanding by Class of Financing Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Gross loans	$ 9,287,225		$ 9,298,212
Less: Allowance for credit losses on loans HFI	(146,134)	$ (140,664)	(134,192)	$ (134,476)	$ (126,272)	$ (125,559)
Net loans held for investment	9,141,091		9,164,020
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Gross loans	1,667,857		1,645,783
Less: Allowance for credit losses on loans HFI	(17,562)	(11,311)	(11,106)	(10,538)	(10,191)	(15,751)
Construction
Financing Receivable, Past Due [Line Items]
Gross loans	1,532,306		1,657,488
Less: Allowance for credit losses on loans HFI	(37,895)	(39,920)	(39,808)	(41,427)	(38,383)	(28,576)
Residential real estate: \| 1-to-4 family mortgage
Financing Receivable, Past Due [Line Items]
Gross loans	1,553,096		1,573,121
Less: Allowance for credit losses on loans HFI	(25,695)	(27,407)	(26,141)	(25,366)	(21,398)	(19,104)
Residential real estate: \| Residential line of credit
Financing Receivable, Past Due [Line Items]
Gross loans	517,082		496,660
Less: Allowance for credit losses on loans HFI	(9,163)	(9,185)	(7,494)	(6,952)	(6,875)	(5,903)
Residential real estate: \| Multi-family mortgage
Financing Receivable, Past Due [Line Items]
Gross loans	501,323		479,572
Less: Allowance for credit losses on loans HFI	(6,848)	(6,828)	(6,490)	(5,874)	(6,503)	(6,976)
Commercial real estate: \| Owner-occupied
Financing Receivable, Past Due [Line Items]
Gross loans	1,206,351		1,114,580
Less: Allowance for credit losses on loans HFI	(10,526)	(8,467)	(7,783)	(8,068)	(7,329)	(12,593)
Commercial real estate: \| Non-owner occupied
Financing Receivable, Past Due [Line Items]
Gross loans	1,911,913		1,964,010
Less: Allowance for credit losses on loans HFI	(22,747)	(22,877)	(21,916)	(22,783)	(22,536)	(25,768)
Consumer and other
Financing Receivable, Past Due [Line Items]
Gross loans	397,297		366,998
Less: Allowance for credit losses on loans HFI	$ (15,698)	$ (14,669)	$ (13,454)	$ (13,468)	$ (13,057)	$ (10,888)