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Loans and Allowance for Credit Losses on Loans HFI - Loans Outstanding by Class of Financing Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Gross loans	$ 9,326,024		$ 9,298,212
Less: Allowance for credit losses on loans HFI	(140,664)	$ (138,809)	(134,192)	$ (126,272)	$ (120,049)	$ (125,559)
Net loans held for investment	9,185,360		9,164,020
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Gross loans	1,693,572		1,645,783
Less: Allowance for credit losses on loans HFI	(11,311)	(11,117)	(11,106)	(10,191)	(12,699)	(15,751)
Construction
Financing Receivable, Past Due [Line Items]
Gross loans	1,636,970		1,657,488
Less: Allowance for credit losses on loans HFI	(39,920)	(41,025)	(39,808)	(38,383)	(31,782)	(28,576)
Residential real estate: \| 1-to-4 family mortgage
Financing Receivable, Past Due [Line Items]
Gross loans	1,548,614		1,573,121
Less: Allowance for credit losses on loans HFI	(27,407)	(27,213)	(26,141)	(21,398)	(21,024)	(19,104)
Residential real estate: \| Residential line of credit
Financing Receivable, Past Due [Line Items]
Gross loans	507,652		496,660
Less: Allowance for credit losses on loans HFI	(9,185)	(9,034)	(7,494)	(6,875)	(6,545)	(5,903)
Residential real estate: \| Multi-family mortgage
Financing Receivable, Past Due [Line Items]
Gross loans	518,025		479,572
Less: Allowance for credit losses on loans HFI	(6,828)	(6,619)	(6,490)	(6,503)	(6,398)	(6,976)
Commercial real estate: \| Owner-occupied
Financing Receivable, Past Due [Line Items]
Gross loans	1,158,782		1,114,580
Less: Allowance for credit losses on loans HFI	(8,467)	(7,952)	(7,783)	(7,329)	(8,416)	(12,593)
Commercial real estate: \| Non-owner occupied
Financing Receivable, Past Due [Line Items]
Gross loans	1,881,978		1,964,010
Less: Allowance for credit losses on loans HFI	(22,877)	(21,868)	(21,916)	(22,536)	(21,290)	(25,768)
Consumer and other
Financing Receivable, Past Due [Line Items]
Gross loans	380,431		366,998
Less: Allowance for credit losses on loans HFI	$ (14,669)	$ (13,981)	$ (13,454)	$ (13,057)	$ (11,895)	$ (10,888)