Loans (Past Due Loans) (Details) - USD ($) $ in Thousands		Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
Past due		$ 10,039	$ 11,345
Current		5,675,193	5,636,361
Total loans	[1]	5,685,232	5,647,706
30-59
Financing Receivable, Past Due [Line Items]
Past due		5,259	6,748
60-89
Financing Receivable, Past Due [Line Items]
Past due		930	1,853
Over 90
Financing Receivable, Past Due [Line Items]
Past due		3,850	2,744
Commercial Real Estate
Financing Receivable, Past Due [Line Items]
Past due		0	0
Current		2,158,518	2,106,359
Total loans	[2]	2,158,518	2,106,359
Commercial Real Estate | 30-59
Financing Receivable, Past Due [Line Items]
Past due		0	0
Commercial Real Estate | 60-89
Financing Receivable, Past Due [Line Items]
Past due		0	0
Commercial Real Estate | Over 90
Financing Receivable, Past Due [Line Items]
Past due		0	0
Commercial & Industrial
Financing Receivable, Past Due [Line Items]
Past due		270	10
Current		613,106	605,062
Total loans	[3]	613,376	605,072
Commercial & Industrial | 30-59
Financing Receivable, Past Due [Line Items]
Past due		270	10
Commercial & Industrial | 60-89
Financing Receivable, Past Due [Line Items]
Past due		0	0
Commercial & Industrial | Over 90
Financing Receivable, Past Due [Line Items]
Past due		0	0
Total Commercial
Financing Receivable, Past Due [Line Items]
Past due		270	10
Current		2,771,624	2,711,421
Total loans		2,771,894	2,711,431
Total Commercial | 30-59
Financing Receivable, Past Due [Line Items]
Past due		270	10
Total Commercial | 60-89
Financing Receivable, Past Due [Line Items]
Past due		0	0
Total Commercial | Over 90
Financing Receivable, Past Due [Line Items]
Past due		0	0
Residential Real Estate
Financing Receivable, Past Due [Line Items]
Past due		6,858	8,116
Current		2,578,666	2,596,362
Total loans	[4]	2,585,524	2,604,478
Residential Real Estate | 30-59
Financing Receivable, Past Due [Line Items]
Past due		2,988	4,369
Residential Real Estate | 60-89
Financing Receivable, Past Due [Line Items]
Past due		817	1,738
Residential Real Estate | Over 90
Financing Receivable, Past Due [Line Items]
Past due		3,053	2,009
Home Equity
Financing Receivable, Past Due [Line Items]
Past due		2,879	3,196
Current		306,423	309,398
Total loans		309,302	312,594
Home Equity | 30-59
Financing Receivable, Past Due [Line Items]
Past due		1,969	2,349
Home Equity | 60-89
Financing Receivable, Past Due [Line Items]
Past due		113	112
Home Equity | Over 90
Financing Receivable, Past Due [Line Items]
Past due		797	735
Other
Financing Receivable, Past Due [Line Items]
Past due		32	23
Current		18,480	19,180
Total loans	[5]	18,512	19,203
Other | 30-59
Financing Receivable, Past Due [Line Items]
Past due		32	20
Other | 60-89
Financing Receivable, Past Due [Line Items]
Past due		0	3
Other | Over 90
Financing Receivable, Past Due [Line Items]
Past due		0	0
Total Consumer
Financing Receivable, Past Due [Line Items]
Past due		2,911	3,219
Current		324,903	328,578
Total loans		327,814	331,797
Total Consumer | 30-59
Financing Receivable, Past Due [Line Items]
Past due		2,001	2,369
Total Consumer | 60-89
Financing Receivable, Past Due [Line Items]
Past due		113	115
Total Consumer | Over 90
Financing Receivable, Past Due [Line Items]
Past due		$ 797	$ 735

[1] Includes net unamortized loan origination costs of $13.1 million and $13.0 million, respectively, at March 31, 2024 and December 31, 2023 and net unamortized premiums on loans purchased from and serviced by other financial institutions of $273 thousand and $286 thousand, respectively, at March 31, 2024 and December 31, 2023.

[2] CRE consists of commercial mortgages primarily secured by income-producing property, as well as construction and development loans. Construction and development loans are made to businesses for land development or the on-site construction of industrial, commercial, or residential buildings.

[3] C&I consists of loans to businesses and individuals, a portion of which are fully or partially collateralized by real estate.

[4] Residential real estate consists of mortgage and homeowner construction loans secured by one- to four-family residential properties.

[5] Other consists of loans to individuals secured by general aviation aircraft and other personal installment loans.