Acquisitions, Salisbury Bancorp, Inc. (Details) shares in Thousands, $ in Thousands		3 Months Ended
	Aug. 11, 2023 USD ($) Office shares	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Recognized amounts of identifiable assets acquired and (liabilities) assumed [Abstract]
Goodwill		$ 361,851	$ 281,204	$ 280,541
Salisbury Bancorp, Inc [Member]
Acquisition of Salisbury Bancorp, Inc. [Abstract]
Number of banking offices | Office	13
Stock issued (in shares) | shares	4,320
Increase in goodwill		$ 1,700
Consideration [Abstract]
Cash paid to shareholders (fractional shares)	$ 15
Common stock issuance	161,723
Total net consideration	161,738
Recognized amounts of identifiable assets acquired and (liabilities) assumed [Abstract]
Cash and cash equivalents	48,665
Securities available for sale	122,667
Loans, net of allowance for credit losses on purchased credit deteriorated loans	1,174,237
Premises and equipment, net	13,026
Bank owned life insurance	30,315
Other assets	37,631
Total identifiable assets acquired	1,462,383
Deposits	(1,308,976)
Borrowings	(55,461)
Other liabilities	(15,949)
Total liabilities assumed	(1,380,386)
Total identifiable assets, net	81,997
Goodwill	79,741
Salisbury Bancorp, Inc [Member] | Core Deposits [Member]
Recognized amounts of identifiable assets acquired and (liabilities) assumed [Abstract]
Intangibles	31,188
Salisbury Bancorp, Inc [Member] | Wealth Management Customer [Member]
Recognized amounts of identifiable assets acquired and (liabilities) assumed [Abstract]
Intangibles	$ 4,654