Loans Receivable, Net - Credit Grades and Risk Characteristics (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Credit Quality Indicator [Line Items]
2021	$ 617,030	$ 1,496,628
2020	1,397,472	1,313,707
2019	1,246,775	817,607
2018	751,041	800,731
2017	759,695	620,952
2016 and prior	2,697,286	2,340,571
Revolving lines of credit	403,238	365,910
Total	7,872,537	7,756,106
Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
2021	68,908	137,993
2020	86,303	42,604
2019	38,761	30,036
2018	27,617	21,076
2017	16,034	34,914
2016 and prior	90,749	61,163
Revolving lines of credit	169,873	142,870
Total	498,245	470,656
Commercial and industrial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	68,908	137,262
2020	85,402	40,737
2019	35,616	27,967
2018	25,960	18,845
2017	13,952	33,568
2016 and prior	88,010	59,339
Revolving lines of credit	161,358	134,140
Total	479,206	451,858
Commercial and industrial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	150
2020	334	583
2019	1,866	826
2018	776	1,422
2017	1,328	907
2016 and prior	706	118
Revolving lines of credit	2,029	1,429
Total	7,039	5,435
Commercial and industrial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	581
2020	567	1,284
2019	1,279	1,243
2018	881	809
2017	754	439
2016 and prior	2,033	1,706
Revolving lines of credit	6,486	7,301
Total	12,000	13,363
Commercial real estate – owner occupied
Financing Receivable, Credit Quality Indicator [Line Items]
2021	20,780	96,888
2020	72,657	152,688
2019	137,930	140,203
2018	137,489	128,477
2017	120,749	125,056
2016 and prior	565,792	481,743
Revolving lines of credit	10,954	20,010
Total	1,066,351	1,145,065
Commercial real estate – owner occupied | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	20,780	96,888
2020	72,657	114,506
2019	120,065	122,962
2018	122,007	124,050
2017	115,902	104,264
2016 and prior	496,736	428,423
Revolving lines of credit	10,127	18,932
Total	958,274	1,010,025
Commercial real estate – owner occupied | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	0
2020	0	3,512
2019	3,488	8,240
2018	6,556	1,023
2017	1,973	17,115
2016 and prior	32,144	17,811
Revolving lines of credit	278	439
Total	44,439	48,140
Commercial real estate – owner occupied | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	0
2020	0	34,670
2019	14,377	9,001
2018	8,926	3,404
2017	2,874	3,677
2016 and prior	36,912	35,509
Revolving lines of credit	549	639
Total	63,638	86,900
Commercial real estate – investor
Financing Receivable, Credit Quality Indicator [Line Items]
2021	399,267	640,241
2020	661,123	653,631
2019	658,527	336,148
2018	325,195	458,715
2017	453,256	297,584
2016 and prior	1,086,610	904,260
Revolving lines of credit	220,373	200,885
Total	3,804,351	3,491,464
Commercial real estate – investor | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	399,267	635,930
2020	656,812	628,435
2019	603,104	317,104
2018	306,120	426,268
2017	420,926	281,876
2016 and prior	997,722	812,062
Revolving lines of credit	214,003	194,913
Total	3,597,954	3,296,588
Commercial real estate – investor | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	0
2020	0	15,979
2019	25,847	17,113
2018	17,113	15,225
2017	14,086	4,234
2016 and prior	41,043	55,872
Revolving lines of credit	0	149
Total	98,089	108,572
Commercial real estate – investor | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	4,311
2020	4,311	9,217
2019	29,576	1,931
2018	1,962	17,222
2017	18,244	11,474
2016 and prior	47,845	36,326
Revolving lines of credit	6,370	5,823
Total	108,308	86,304
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total	2,503,590	2,648,921
Consumer | Residential real estate
Financing Receivable, Credit Quality Indicator [Line Items]
2021	122,744	596,552
2020	553,741	438,125
2019	387,481	227,924
2018	188,276	166,994
2017	146,061	146,683
2016 and prior	791,045	733,181
Revolving lines of credit	0	0
Total	2,189,348	2,309,459
Consumer | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
2021	5,331	24,954
2020	23,648	26,659
2019	24,076	83,296
2018	72,464	25,469
2017	23,595	16,715
2016 and prior	163,090	160,224
Revolving lines of credit	2,038	2,145
Total	314,242	339,462
Consumer | Pass | Residential real estate
Financing Receivable, Credit Quality Indicator [Line Items]
2021	122,744	595,982
2020	553,741	437,593
2019	387,283	226,435
2018	188,276	166,773
2017	145,840	146,237
2016 and prior	789,192	729,037
Revolving lines of credit	0	0
Total	2,187,076	2,302,057
Consumer | Pass | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
2021	5,331	24,954
2020	23,648	26,659
2019	24,022	83,296
2018	72,429	25,469
2017	23,595	16,565
2016 and prior	159,762	156,276
Revolving lines of credit	2,038	2,145
Total	310,825	335,364
Consumer | Special Mention | Residential real estate
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	0
2020	0	532
2019	198	0
2018	0	0
2017	0	446
2016 and prior	335	2,186
Revolving lines of credit	0	0
Total	533	3,164
Consumer | Special Mention | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	0
2020	0	0
2019	54	0
2018	18	0
2017	0	150
2016 and prior	49	382
Revolving lines of credit	0	0
Total	121	532
Consumer | Substandard | Residential real estate
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	570
2020	0	0
2019	0	1,489
2018	0	221
2017	221	0
2016 and prior	1,518	1,958
Revolving lines of credit	0	0
Total	1,739	4,238
Consumer | Substandard | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	0
2020	0	0
2019	0	0
2018	17	0
2017	0	0
2016 and prior	3,279	3,566
Revolving lines of credit	0	0
Total	$ 3,296	$ 3,566