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Loans - Loans by Credit Quality Indicator (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 5,231,331,000	$ 5,707,762,000
Charge-offs	12,234,000	12,394,000	$ 10,131,000
Total, Current period gross recoveries	948,000	1,268,000	4,241,000
Loans at fair value	0	17,011,000
Real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total	3,133,334,000	2,787,908,000
Real estate | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	558,263,000	396,947,000
Year two	369,753,000	292,185,000
Year three	278,817,000	321,165,000
Year four	247,391,000	181,722,000
Year five	127,435,000	47,608,000
Prior	88,786,000	109,743,000
Revolving Loans Amortized Cost Basis	23,067,000	21,558,000
Total	1,693,512,000	1,370,928,000
2021, Current period gross charge-offs	0
2020, Current period gross charge-offs	0	0
2019, Current period gross charge-offs	0	0
2018, Current period gross charge-offs	120,000	0
2017, Current period gross charge-offs	24,000	3,622,000
2016, Current period gross charge-offs		199,000
Prior, Current period gross charge-offs	26,000	1,103,000
Revolving Loans Amortized Cost Basis, Current period gross charge-offs	0	0
Charge-offs	170,000	4,924,000	1,420,000
2021, Current period gross recoveries	0
2020, Current period gross recoveries	0	0
2019, Current period gross recoveries	0	0
2018, Current period gross recoveries	48,000	0
2017, Current period gross recoveries	3,000	0
2016, Current period gross recoveries		0
Prior, Current period gross recoveries	14,000	19,000
Revolving Loans Amortized Cost Basis, Current period gross recoveries	0	0
Total, Current period gross recoveries	65,000	19,000	341,000
2021, Current period net charge-offs (recoveries)	0
2020, Current period net charge-offs (recoveries)	0	0
2019, Current period net charge-offs (recoveries)	0	0
2018, Current period net charge-offs (recoveries)	72,000	0
2017, Current period net charge-offs (recoveries)	21,000	3,622,000
2016, Current period net charge-offs (recoveries)		199,000
Prior, Current period net charge-offs (recoveries)	12,000	1,084,000
Revolving Loans Amortized Cost Basis, Current period net charge-offs (recoveries)	0	0
Total, Current period net charge-offs (recoveries)	105,000	4,905,000
Loans at fair value	0	17,000,000
Real estate | Commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	556,218,000	393,317,000
Year two	369,128,000	290,394,000
Year three	278,045,000	312,051,000
Year four	236,543,000	154,445,000
Year five	111,308,000	46,132,000
Prior	86,498,000	106,994,000
Revolving Loans Amortized Cost Basis	22,904,000	18,419,000
Total	1,660,644,000	1,321,752,000
Real estate | Commercial real estate | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	824,000
Year two	0	113,000
Year three	0	2,410,000
Year four	8,392,000	20,691,000
Year five	15,828,000	0
Prior	0	1,656,000
Revolving Loans Amortized Cost Basis	0	2,145,000
Total	24,220,000	27,839,000
Real estate | Commercial real estate | Classified
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	2,045,000	2,806,000
Year two	625,000	1,678,000
Year three	772,000	6,704,000
Year four	2,456,000	6,586,000
Year five	299,000	1,476,000
Prior	2,288,000	1,093,000
Revolving Loans Amortized Cost Basis	163,000	994,000
Total	8,648,000	21,337,000
Real estate | Construction/land/land development
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	256,655,000	189,634,000
Year two	102,756,000	162,513,000
Year three	93,840,000	138,861,000
Year four	33,805,000	15,417,000
Year five	6,583,000	1,955,000
Prior	553,000	1,325,000
Revolving Loans Amortized Cost Basis	35,891,000	22,155,000
Total	530,083,000	531,860,000
2021, Current period gross charge-offs	0
2020, Current period gross charge-offs	0	0
2019, Current period gross charge-offs	0	0
2018, Current period gross charge-offs	0	0
2017, Current period gross charge-offs	0	0
2016, Current period gross charge-offs		0
Prior, Current period gross charge-offs	0	0
Revolving Loans Amortized Cost Basis, Current period gross charge-offs	0	0
Charge-offs	0	0	38,000
2021, Current period gross recoveries	0
2020, Current period gross recoveries	0	0
2019, Current period gross recoveries	0	0
2018, Current period gross recoveries	0	0
2017, Current period gross recoveries	0	0
2016, Current period gross recoveries		0
Prior, Current period gross recoveries	0	1,000
Revolving Loans Amortized Cost Basis, Current period gross recoveries	0	0
Total, Current period gross recoveries	0	1,000	40,000
2021, Current period net charge-offs (recoveries)	0
2020, Current period net charge-offs (recoveries)	0	0
2019, Current period net charge-offs (recoveries)	0	0
2018, Current period net charge-offs (recoveries)	0	0
2017, Current period net charge-offs (recoveries)	0	0
2016, Current period net charge-offs (recoveries)		0
Prior, Current period net charge-offs (recoveries)	0	(1,000)
Revolving Loans Amortized Cost Basis, Current period net charge-offs (recoveries)	0	0
Total, Current period net charge-offs (recoveries)	0	(1,000)
Real estate | Construction/land/land development | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	256,212,000	189,311,000
Year two	102,459,000	150,281,000
Year three	85,442,000	138,000,000
Year four	32,128,000	12,907,000
Year five	5,422,000	1,812,000
Prior	553,000	1,157,000
Revolving Loans Amortized Cost Basis	30,729,000	18,892,000
Total	512,945,000	512,360,000
Real estate | Construction/land/land development | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	323,000
Year two	0	10,421,000
Year three	8,126,000	135,000
Year four	0	1,003,000
Year five	1,003,000	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Total	9,129,000	11,882,000
Real estate | Construction/land/land development | Classified
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	443,000	0
Year two	297,000	1,811,000
Year three	272,000	726,000
Year four	1,677,000	1,507,000
Year five	158,000	143,000
Prior	0	168,000
Revolving Loans Amortized Cost Basis	5,162,000	3,263,000
Total	8,009,000	7,618,000
Real estate | Residential real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	315,296,000	369,697,000
Year two	252,480,000	145,771,000
Year three	111,957,000	106,461,000
Year four	55,784,000	104,658,000
Year five	47,338,000	52,153,000
Prior	66,296,000	52,430,000
Revolving Loans Amortized Cost Basis	60,588,000	53,950,000
Total	909,739,000	885,120,000
2021, Current period gross charge-offs	0
2020, Current period gross charge-offs	7,000	94,000
2019, Current period gross charge-offs	61,000	271,000
2018, Current period gross charge-offs	0	0
2017, Current period gross charge-offs	0	283,000
2016, Current period gross charge-offs		0
Prior, Current period gross charge-offs	10,000	44,000
Revolving Loans Amortized Cost Basis, Current period gross charge-offs	0	0
Charge-offs	78,000	692,000	265,000
2021, Current period gross recoveries	0
2020, Current period gross recoveries	21,000	0
2019, Current period gross recoveries	19,000	0
2018, Current period gross recoveries	0	0
2017, Current period gross recoveries	25,000	0
2016, Current period gross recoveries		0
Prior, Current period gross recoveries	52,000	202,000
Revolving Loans Amortized Cost Basis, Current period gross recoveries	0	0
Total, Current period gross recoveries	117,000	202,000	185,000
2021, Current period net charge-offs (recoveries)	0
2020, Current period net charge-offs (recoveries)	(14,000)	94,000
2019, Current period net charge-offs (recoveries)	42,000	271,000
2018, Current period net charge-offs (recoveries)	0	0
2017, Current period net charge-offs (recoveries)	(25,000)	283,000
2016, Current period net charge-offs (recoveries)		0
Prior, Current period net charge-offs (recoveries)	(42,000)	(158,000)
Revolving Loans Amortized Cost Basis, Current period net charge-offs (recoveries)	0	0
Total, Current period net charge-offs (recoveries)	(39,000)	490,000
Real estate | Residential real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	313,898,000	367,652,000
Year two	252,115,000	143,368,000
Year three	109,564,000	103,450,000
Year four	52,515,000	102,272,000
Year five	45,042,000	41,522,000
Prior	59,690,000	50,094,000
Revolving Loans Amortized Cost Basis	60,342,000	53,854,000
Total	893,166,000	862,212,000
Real estate | Residential real estate | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	188,000
Year two	174,000	0
Year three	0	29,000
Year four	421,000	1,875,000
Year five	477,000	9,287,000
Prior	0	803,000
Revolving Loans Amortized Cost Basis	0	0
Total	1,072,000	12,182,000
Real estate | Residential real estate | Classified
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	1,398,000	1,857,000
Year two	191,000	2,403,000
Year three	2,393,000	2,982,000
Year four	2,848,000	511,000
Year five	1,819,000	1,344,000
Prior	6,606,000	1,533,000
Revolving Loans Amortized Cost Basis	246,000	96,000
Total	15,501,000	10,726,000
Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	463,014,000	862,076,000
Year two	167,247,000	168,031,000
Year three	96,466,000	142,389,000
Year four	70,159,000	35,286,000
Year five	18,591,000	15,877,000
Prior	27,022,000	48,514,000
Revolving Loans Amortized Cost Basis	611,736,000	545,689,000
Total	1,454,235,000	1,817,862,000
2021, Current period gross charge-offs	9,000
2020, Current period gross charge-offs	1,172,000	189,000
2019, Current period gross charge-offs	54,000	204,000
2018, Current period gross charge-offs	5,000	87,000
2017, Current period gross charge-offs	1,467,000	121,000
2016, Current period gross charge-offs		3,228,000
Prior, Current period gross charge-offs	6,354,000	469,000
Revolving Loans Amortized Cost Basis, Current period gross charge-offs	2,862,000	2,404,000
Charge-offs	11,923,000	6,702,000	8,231,000
2021, Current period gross recoveries	0
2020, Current period gross recoveries	18,000	0
2019, Current period gross recoveries	51,000	42,000
2018, Current period gross recoveries	3,000	20,000
2017, Current period gross recoveries	102,000	81,000
2016, Current period gross recoveries		185,000
Prior, Current period gross recoveries	204,000	112,000
Revolving Loans Amortized Cost Basis, Current period gross recoveries	339,000	582,000
Total, Current period gross recoveries	717,000	1,022,000	3,627,000
2021, Current period net charge-offs (recoveries)	9,000
2020, Current period net charge-offs (recoveries)	1,154,000	189,000
2019, Current period net charge-offs (recoveries)	3,000	162,000
2018, Current period net charge-offs (recoveries)	2,000	67,000
2017, Current period net charge-offs (recoveries)	1,365,000	40,000
2016, Current period net charge-offs (recoveries)		3,043,000
Prior, Current period net charge-offs (recoveries)	6,150,000	357,000
Revolving Loans Amortized Cost Basis, Current period net charge-offs (recoveries)	2,523,000	1,822,000
Total, Current period net charge-offs (recoveries)	11,206,000	5,680,000
Commercial and industrial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	448,377,000	851,780,000
Year two	164,910,000	153,722,000
Year three	93,488,000	110,092,000
Year four	64,791,000	29,413,000
Year five	14,742,000	9,927,000
Prior	24,014,000	26,964,000
Revolving Loans Amortized Cost Basis	599,144,000	511,220,000
Total	1,409,466,000	1,693,118,000
Commercial and industrial | Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	259,000	4,860,000
Year two	2,170,000	2,059,000
Year three	0	26,438,000
Year four	1,519,000	423,000
Year five	0	0
Prior	0	14,843,000
Revolving Loans Amortized Cost Basis	3,752,000	8,077,000
Total	7,700,000	56,700,000
Commercial and industrial | Classified
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	14,378,000	5,436,000
Year two	167,000	12,250,000
Year three	2,978,000	5,859,000
Year four	3,849,000	5,450,000
Year five	3,849,000	5,950,000
Prior	3,008,000	6,707,000
Revolving Loans Amortized Cost Basis	8,840,000	26,392,000
Total	37,069,000	68,044,000
Mortgage warehouse lines of credit
Financing Receivable, Credit Quality Indicator [Line Items]
Total	627,078,000	1,084,001,000
2021, Current period gross charge-offs	0
2020, Current period gross charge-offs	0	0
2019, Current period gross charge-offs	0	0
2018, Current period gross charge-offs	0	0
2017, Current period gross charge-offs	0	0
2016, Current period gross charge-offs		0
Prior, Current period gross charge-offs	0	0
Revolving Loans Amortized Cost Basis, Current period gross charge-offs	0	0
Charge-offs	0	0	29,000
2021, Current period gross recoveries	0
2020, Current period gross recoveries	0	0
2019, Current period gross recoveries	0	0
2018, Current period gross recoveries	0	0
2017, Current period gross recoveries	0	0
2016, Current period gross recoveries		0
Prior, Current period gross recoveries	0	0
Revolving Loans Amortized Cost Basis, Current period gross recoveries	0	0
Total, Current period gross recoveries	0	0	0
2021, Current period net charge-offs (recoveries)	0
2020, Current period net charge-offs (recoveries)	0	0
2019, Current period net charge-offs (recoveries)	0	0
2018, Current period net charge-offs (recoveries)	0	0
2017, Current period net charge-offs (recoveries)	0	0
2016, Current period net charge-offs (recoveries)		0
Prior, Current period net charge-offs (recoveries)	0	0
Revolving Loans Amortized Cost Basis, Current period net charge-offs (recoveries)	0	0
Total, Current period net charge-offs (recoveries)	0	0
Mortgage warehouse lines of credit | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	627,078,000	1,084,001,000
Total	627,078,000	1,084,001,000
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	7,002,000	6,730,000
Year two	2,190,000	3,326,000
Year three	1,468,000	1,578,000
Year four	443,000	203,000
Year five	55,000	122,000
Prior	68,000	84,000
Revolving Loans Amortized Cost Basis	5,458,000	5,948,000
Total	16,684,000	17,991,000
2021, Current period gross charge-offs	0
2020, Current period gross charge-offs	5,000	0
2019, Current period gross charge-offs	29,000	39,000
2018, Current period gross charge-offs	2,000	23,000
2017, Current period gross charge-offs	0	8,000
2016, Current period gross charge-offs		0
Prior, Current period gross charge-offs	9,000	4,000
Revolving Loans Amortized Cost Basis, Current period gross charge-offs	18,000	2,000
Charge-offs	63,000	76,000	148,000
2021, Current period gross recoveries	0
2020, Current period gross recoveries	0	0
2019, Current period gross recoveries	20,000	0
2018, Current period gross recoveries	7,000	1,000
2017, Current period gross recoveries	1,000	7,000
2016, Current period gross recoveries		5,000
Prior, Current period gross recoveries	17,000	7,000
Revolving Loans Amortized Cost Basis, Current period gross recoveries	4,000	4,000
Total, Current period gross recoveries	49,000	24,000	$ 48,000
2021, Current period net charge-offs (recoveries)	0
2020, Current period net charge-offs (recoveries)	5,000	0
2019, Current period net charge-offs (recoveries)	9,000	39,000
2018, Current period net charge-offs (recoveries)	(5,000)	22,000
2017, Current period net charge-offs (recoveries)	(1,000)	1,000
2016, Current period net charge-offs (recoveries)		(5,000)
Prior, Current period net charge-offs (recoveries)	(8,000)	(3,000)
Revolving Loans Amortized Cost Basis, Current period net charge-offs (recoveries)	14,000	(2,000)
Total, Current period net charge-offs (recoveries)	14,000	52,000
Consumer | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	6,976,000	6,702,000
Year two	2,169,000	3,318,000
Year three	1,467,000	1,578,000
Year four	443,000	203,000
Year five	55,000	116,000
Prior	67,000	83,000
Revolving Loans Amortized Cost Basis	5,407,000	5,935,000
Total	16,584,000	17,935,000
Consumer | Classified
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	26,000	28,000
Year two	21,000	8,000
Year three	1,000	0
Year four	0	0
Year five	0	6,000
Prior	1,000	1,000
Revolving Loans Amortized Cost Basis	51,000	13,000
Total	$ 100,000	$ 56,000

X

- Definition

Financing Receivable, Allowance For Credit Loss, Recovery, Originated Five Or More Years Before Latest Fiscal Year

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No definition available.

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- Definition

Financing Receivable, Allowance For Credit Loss, Writeoff, After Recovery, Originated Five Or More Years Before Latest Fiscal Year

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Financing Receivable, Allowance For Credit Loss, Writeoff, After Recovery, Originated Five Years Before Latest Fiscal Year

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- Definition

Financing Receivable, Allowance For Credit Loss, Writeoff, After Recovery, Originated Four Years Before Latest Fiscal Year

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- Definition

Financing Receivable, Allowance For Credit Loss, Writeoff, After Recovery, Originated in Current Fiscal Year

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- Definition

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- Definition

Financing Receivable, Allowance For Credit Loss, Writeoff, After Recovery, Originated Two Years Before Latest Fiscal Year

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