Revenue from Contracts with Customers Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 54,181	$ 45,043	$ 106,588	$ 98,210
Non-interest income	72,702	60,076	149,459	133,454
Deposit service fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	41,439	35,839	81,908	78,409
Wealth and investment services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	10,087	7,102	19,490	15,841
Other non interest income [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,655	2,102	5,190	3,960
Non-interest income within the scope of other GAAP topics [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	18,521
Non-interest income		15,033	42,871	35,244
Operating Segments [Member] | Commercial Banking
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	14,476	10,946	28,291	23,859
Non-interest income	25,713	21,849	50,890	44,265
Operating Segments [Member] | Commercial Banking | Deposit service fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	4,104	3,443	8,205	7,354
Operating Segments [Member] | Commercial Banking | Wealth and investment services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	10,096	7,140	19,508	15,886
Operating Segments [Member] | Commercial Banking | Other non interest income [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	276	363	578	619
Operating Segments [Member] | Commercial Banking | Non-interest income within the scope of other GAAP topics [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	11,237
Non-interest income		10,903	22,599	20,406
Operating Segments [Member] | HSA Bank
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	26,554	23,103	53,559	49,486
Non-interest income	26,554	23,103	53,559	49,486
Operating Segments [Member] | HSA Bank | Deposit service fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	24,478	21,741	49,496	46,583
Operating Segments [Member] | HSA Bank | Wealth and investment services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Operating Segments [Member] | HSA Bank | Other non interest income [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,076	1,362	4,063	2,903
Operating Segments [Member] | HSA Bank | Non-interest income within the scope of other GAAP topics [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0
Non-interest income		0	0	0
Operating Segments [Member] | Retail Banking
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	13,037	11,125	24,586	24,926
Non-interest income	16,763	16,281	32,834	34,724
Operating Segments [Member] | Retail Banking | Deposit service fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	12,734	10,748	24,037	24,488
Operating Segments [Member] | Retail Banking | Wealth and investment services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Operating Segments [Member] | Retail Banking | Other non interest income [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	303	377	549	438
Operating Segments [Member] | Retail Banking | Non-interest income within the scope of other GAAP topics [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	3,726
Non-interest income		5,156	8,248	9,798
Corporate, Non-Segment [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	114	(131)	152	(61)
Non-interest income	3,672	(1,157)	12,176	4,979
Corporate, Non-Segment [Member] | Deposit service fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	123	(93)	170	(16)
Corporate, Non-Segment [Member] | Wealth and investment services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	(9)	(38)	(18)	(45)
Corporate, Non-Segment [Member] | Other non interest income [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Corporate, Non-Segment [Member] | Non-interest income within the scope of other GAAP topics [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 3,558
Non-interest income		$ (1,026)	$ 12,024	$ 5,040