Portfolio Loans - Summary of Term Loans by Origination Year (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Total		$ 5,314,337
Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 1,453,800
2019	479,317
2018	274,958
2017	144,305
2016	49,160
Prior	59,505
Financing Receivable, Converted	15,399
Revolving Loans	610,050
Total	3,086,494
Commercial and industrial \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	1,402,276
2019	454,729
2018	262,258
2017	132,832
2016	25,057
Prior	58,315
Financing Receivable, Converted	14,118
Revolving Loans	527,170
Total	2,876,755
Commercial and industrial \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	44,922
2019	15,369
2018	9,585
2017	7,509
2016	19,613
Prior	110
Financing Receivable, Converted	0
Revolving Loans	60,448
Total	157,556
Commercial and industrial \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	6,602
2019	9,219
2018	3,115
2017	3,964
2016	4,490
Prior	1,080
Financing Receivable, Converted	1,281
Revolving Loans	22,432
Total	52,183
Commercial Real Estate-Investor Owned Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	514,175
2019	363,843
2018	204,677
2017	137,548
2016	149,180
Prior	181,429
Financing Receivable, Converted	6,509
Revolving Loans	32,058
Total	1,589,419
Commercial Real Estate-Investor Owned Portfolio Segment [Member] \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	481,867
2019	338,843
2018	189,305
2017	131,718
2016	138,288
Prior	161,439
Financing Receivable, Converted	6,509
Revolving Loans	32,058
Total	1,480,027
Commercial Real Estate-Investor Owned Portfolio Segment [Member] \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	32,308
2019	19,722
2018	6,656
2017	0
2016	9,647
Prior	17,370
Financing Receivable, Converted	0
Revolving Loans	0
Total	85,703
Commercial Real Estate-Investor Owned Portfolio Segment [Member] \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	5,278
2018	8,716
2017	5,830
2016	1,245
Prior	2,620
Financing Receivable, Converted	0
Revolving Loans	0
Total	23,689
Commercial Real Estate-Owner Occupied Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	435,219
2019	299,685
2018	224,116
2017	191,720
2016	110,117
Prior	186,776
Financing Receivable, Converted	4,448
Revolving Loans	46,327
Total	1,498,408
Commercial Real Estate-Owner Occupied Portfolio Segment [Member] \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	419,142
2019	287,001
2018	215,181
2017	179,382
2016	104,470
Prior	167,456
Financing Receivable, Converted	2,672
Revolving Loans	45,323
Total	1,420,627
Commercial Real Estate-Owner Occupied Portfolio Segment [Member] \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	13,657
2019	5,257
2018	3,113
2017	6,198
2016	4,338
Prior	8,460
Financing Receivable, Converted	1,776
Revolving Loans	941
Total	43,740
Commercial Real Estate-Owner Occupied Portfolio Segment [Member] \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	2,420
2019	7,427
2018	5,822
2017	6,140
2016	1,309
Prior	10,860
Financing Receivable, Converted	0
Revolving Loans	63
Total	34,041
Construction Real Estate Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	225,669
2019	158,570
2018	80,142
2017	30,212
2016	11,539
Prior	11,674
Financing Receivable, Converted	0
Revolving Loans	28,880
Total	546,686
Construction Real Estate Portfolio Segment [Member] \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	223,069
2019	156,360
2018	45,460
2017	18,579
2016	11,539
Prior	9,144
Financing Receivable, Converted	0
Revolving Loans	28,880
Total	493,031
Construction Real Estate Portfolio Segment [Member] \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	2,544
2019	86
2018	34,179
2017	11,632
2016	0
Prior	2,499
Financing Receivable, Converted	0
Revolving Loans	0
Total	50,940
Construction Real Estate Portfolio Segment [Member] \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	56
2019	2,124
2018	503
2017	1
2016	0
Prior	31
Financing Receivable, Converted	0
Revolving Loans	0
Total	2,715
Residential
Financing Receivable, Credit Quality Indicator [Line Items]
2020	57,840
2019	29,480
2018	18,365
2017	17,152
2016	28,855
Prior	97,441
Financing Receivable, Converted	1,459
Revolving Loans	67,666
Total	318,258
Residential \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	57,059
2019	27,907
2018	17,718
2017	17,138
2016	27,443
Prior	92,657
Financing Receivable, Converted	1,172
Revolving Loans	66,902
Total	307,996
Residential \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	210
2019	840
2018	526
2017	0
2016	514
Prior	1,603
Financing Receivable, Converted	287
Revolving Loans	511
Total	4,491
Residential \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	571
2019	733
2018	121
2017	14
2016	898
Prior	3,181
Financing Receivable, Converted	0
Revolving Loans	253
Total	5,771
Other
Financing Receivable, Credit Quality Indicator [Line Items]
2020	43,526
2019	28,214
2018	30,101
2017	9,659
2016	5,641
Prior	19,681
Financing Receivable, Converted	8
Revolving Loans	40,784
Total	177,614
Other \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	43,526
2019	28,195
2018	30,074
2017	9,646
2016	5,641
Prior	17,027
Financing Receivable, Converted	0
Revolving Loans	40,779
Total	174,888
Other \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	1
2018	8
2017	0
2016	0
Prior	2,637
Financing Receivable, Converted	0
Revolving Loans	1
Total	2,647
Other \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	18
2018	19
2017	13
2016	0
Prior	17
Financing Receivable, Converted	8
Revolving Loans	4
Total	$ 79

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