Loans - Summary of Term Loans by Origination Year (Details) $ in Thousands	Mar. 31, 2021 USD ($)
Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 534,877
2019	1,084,983
2018	420,993
2017	215,281
2016	125,942
Prior	82,255
Financing Receivable, Converted	9,030
Revolving Loans	592,598
Total	3,065,959
Commercial and industrial \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	510,640
2019	1,044,599
2018	403,420
2017	196,752
2016	121,210
Prior	65,492
Financing Receivable, Converted	8,432
Revolving Loans	515,327
Total	2,865,872
Commercial and industrial \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	20,506
2019	34,164
2018	8,303
2017	15,706
2016	4,378
Prior	15,002
Financing Receivable, Converted	191
Revolving Loans	57,994
Total	156,244
Commercial and industrial \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	3,731
2019	6,220
2018	9,270
2017	2,823
2016	354
Prior	1,761
Financing Receivable, Converted	407
Revolving Loans	19,277
Total	43,843
Commercial Real Estate-Investor Owned Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	128,616
2019	509,782
2018	369,703
2017	208,844
2016	129,903
Prior	279,775
Financing Receivable, Converted	3,712
Revolving Loans	38,880
Total	1,669,215
Commercial Real Estate-Investor Owned Portfolio Segment [Member] \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	125,834
2019	471,216
2018	351,386
2017	195,605
2016	129,903
Prior	252,747
Financing Receivable, Converted	3,712
Revolving Loans	38,880
Total	1,569,283
Commercial Real Estate-Investor Owned Portfolio Segment [Member] \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	2,782
2019	32,554
2018	13,017
2017	6,588
2016	0
Prior	24,282
Financing Receivable, Converted	0
Revolving Loans	0
Total	79,223
Commercial Real Estate-Investor Owned Portfolio Segment [Member] \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	6,012
2018	5,300
2017	6,651
2016	0
Prior	2,746
Financing Receivable, Converted	0
Revolving Loans	0
Total	20,709
Commercial Real Estate-Owner Occupied Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	91,342
2019	433,216
2018	265,995
2017	228,185
2016	175,839
Prior	279,360
Financing Receivable, Converted	0
Revolving Loans	43,818
Total	1,517,755
Commercial Real Estate-Owner Occupied Portfolio Segment [Member] \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	88,848
2019	422,455
2018	253,188
2017	205,203
2016	161,983
Prior	258,470
Financing Receivable, Converted	0
Revolving Loans	42,003
Total	1,432,150
Commercial Real Estate-Owner Occupied Portfolio Segment [Member] \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	2,111
2019	8,967
2018	5,212
2017	17,006
2016	6,130
Prior	9,732
Financing Receivable, Converted	0
Revolving Loans	1,752
Total	50,910
Commercial Real Estate-Owner Occupied Portfolio Segment [Member] \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	383
2019	1,794
2018	7,595
2017	5,976
2016	7,726
Prior	11,158
Financing Receivable, Converted	0
Revolving Loans	63
Total	34,695
Construction Real Estate Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	92,475
2019	181,015
2018	123,119
2017	51,806
2016	19,130
Prior	18,451
Financing Receivable, Converted	0
Revolving Loans	24,505
Total	510,501
Construction Real Estate Portfolio Segment [Member] \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	76,142
2019	180,898
2018	120,004
2017	30,559
2016	7,843
Prior	15,954
Financing Receivable, Converted	0
Revolving Loans	24,405
Total	455,805
Construction Real Estate Portfolio Segment [Member] \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	16,333
2019	62
2018	85
2017	20,748
2016	11,287
Prior	2,468
Financing Receivable, Converted	0
Revolving Loans	0
Total	50,983
Construction Real Estate Portfolio Segment [Member] \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	55
2018	3,030
2017	499
2016	0
Prior	29
Financing Receivable, Converted	0
Revolving Loans	100
Total	3,713
Residential Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
2020	15,386
2019	57,388
2018	25,085
2017	16,011
2016	14,858
Prior	114,843
Financing Receivable, Converted	112
Revolving Loans	58,448
Total	302,131
Residential Portfolio Segment \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	15,166
2019	56,188
2018	23,567
2017	15,421
2016	14,844
Prior	109,575
Financing Receivable, Converted	112
Revolving Loans	57,997
Total	292,870
Residential Portfolio Segment \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	313
2018	801
2017	513
2016	0
Prior	1,725
Financing Receivable, Converted	0
Revolving Loans	379
Total	3,731
Residential Portfolio Segment \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	220
2019	887
2018	717
2017	77
2016	14
Prior	3,543
Financing Receivable, Converted	0
Revolving Loans	72
Total	5,530
Other
Financing Receivable, Credit Quality Indicator [Line Items]
2020	33,630
2019	56,052
2018	21,770
2017	27,528
2016	9,291
Prior	27,911
Financing Receivable, Converted	0
Revolving Loans	31,646
Total	207,828
Other \| Pass (1-6)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	33,630
2019	56,052
2018	21,753
2017	27,503
2016	9,290
Prior	25,300
Financing Receivable, Converted	0
Revolving Loans	31,640
Total	205,168
Other \| Watch (7)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	1
2017	7
2016	0
Prior	2,588
Financing Receivable, Converted	0
Revolving Loans	5
Total	2,601
Other \| Classified (8 & 9)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	16
2017	18
2016	1
Prior	23
Financing Receivable, Converted	0
Revolving Loans	1
Total	$ 59

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Amount of financing receivable originated four years prior to latest fiscal year.

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Amount, before allowance for credit loss, of financing receivable.

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