Loans Receivable - Credit Quality Indicators (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	$ 1,279,419
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	804,177
Financing Receivable, Originated Two Years before Latest Fiscal Year	460,216
Financing Receivable, Originated Three Years before Latest Fiscal Year	381,636
Pass		$ 3,625,083
Special Mention		48,859
Special Mention		93,413
Doubtful/Loss		524
Loans and Leases Receivable, Gross, Total	4,468,647	3,767,879
Potential problem loans receivable	182,300	87,800
Loans and Leases Receivable, Net of Deferred Income	4,468,647	3,767,879
Commercial business
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	1,143,639
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	495,683
Financing Receivable, Originated Two Years before Latest Fiscal Year	349,200
Financing Receivable, Originated Three Years before Latest Fiscal Year	331,325
Pass		2,811,483
Special Mention		46,661
Special Mention		88,089
Doubtful/Loss		0
Loans and Leases Receivable, Gross, Total	3,715,206	2,946,233
Loans and Leases Receivable, Net of Deferred Income	3,715,206	2,946,233
Commercial business \| Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	135,600
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	148,916
Financing Receivable, Originated Two Years before Latest Fiscal Year	85,060
Financing Receivable, Originated Three Years before Latest Fiscal Year	57,750
Pass		771,559
Special Mention		16,340
Special Mention		64,321
Doubtful/Loss		0
Loans and Leases Receivable, Gross, Total		852,220
Loans and Leases Receivable, Net of Deferred Income	733,098	852,220
Commercial business \| Owner-occupied CRE
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	95,370
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	171,635
Financing Receivable, Originated Two Years before Latest Fiscal Year	111,330
Financing Receivable, Originated Three Years before Latest Fiscal Year	98,689
Pass		765,411
Special Mention		24,659
Special Mention		15,164
Doubtful/Loss		0
Loans and Leases Receivable, Gross, Total		805,234
Loans and Leases Receivable, Net of Deferred Income	856,684	805,234
Commercial business \| Non-owner occupied CRE
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	197,548
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	175,132
Financing Receivable, Originated Two Years before Latest Fiscal Year	152,810
Financing Receivable, Originated Three Years before Latest Fiscal Year	174,886
Pass		1,274,513
Special Mention		5,662
Special Mention		8,604
Doubtful/Loss		0
Loans and Leases Receivable, Gross, Total		1,288,779
Loans and Leases Receivable, Net of Deferred Income	1,410,303	1,288,779
Residential real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	30,141
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	41,829
Financing Receivable, Originated Two Years before Latest Fiscal Year	15,730
Financing Receivable, Originated Three Years before Latest Fiscal Year	10,421
Pass		130,818
Special Mention		0
Special Mention		842
Doubtful/Loss		0
Loans and Leases Receivable, Gross, Total		131,660
Loans and Leases Receivable, Net of Deferred Income	122,756	131,660
Real estate construction and land development
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	61,863
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	189,178
Financing Receivable, Originated Two Years before Latest Fiscal Year	41,407
Financing Receivable, Originated Three Years before Latest Fiscal Year	8,683
Pass		271,641
Special Mention		2,198
Special Mention		807
Doubtful/Loss		0
Loans and Leases Receivable, Gross, Total	305,713	274,646
Loans and Leases Receivable, Net of Deferred Income	305,713	274,646
Real estate construction and land development \| Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	33,801
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	36,697
Financing Receivable, Originated Two Years before Latest Fiscal Year	2,725
Financing Receivable, Originated Three Years before Latest Fiscal Year	3,023
Pass		101,973
Special Mention		1,516
Special Mention		807
Doubtful/Loss		0
Loans and Leases Receivable, Gross, Total		104,296
Loans and Leases Receivable, Net of Deferred Income	78,259	104,296
Real estate construction and land development \| Commercial and multifamily
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	28,062
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	152,481
Financing Receivable, Originated Two Years before Latest Fiscal Year	38,682
Financing Receivable, Originated Three Years before Latest Fiscal Year	5,660
Pass		169,668
Special Mention		682
Special Mention		0
Doubtful/Loss		0
Loans and Leases Receivable, Gross, Total		170,350
Loans and Leases Receivable, Net of Deferred Income	227,454	170,350
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	43,776
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	77,487
Financing Receivable, Originated Two Years before Latest Fiscal Year	53,879
Financing Receivable, Originated Three Years before Latest Fiscal Year	31,207
Pass		411,141
Special Mention		0
Special Mention		3,675
Doubtful/Loss		524
Loans and Leases Receivable, Gross, Total		415,340
Loans and Leases Receivable, Net of Deferred Income	$ 324,972	$ 415,340

Financing receivables doubtful rated.

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Potential problem loans receivable.

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Amount of financing receivable originated in current fiscal year.

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Amount of financing receivable originated in fiscal year prior to current fiscal year.

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Amount of financing receivable originated three years prior to current fiscal year.

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Amount of financing receivable originated two years prior to current fiscal year.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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