ACCUMULATED OTHER COMPREHENSIVE INCOME - Changes in accumulated other comprehensive income by component, net of tax (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period		$ 385,693	$ 420,214	$ 393,718	$ 429,471
Other comprehensive income (loss) before reclassification		1,349	(8,427)	3,948	(18,929)
Amounts reclassified from accumulated other comprehensive income		(1,348)	184	(2,354)	554
Total other comprehensive income (loss), after tax		1	(8,243)	1,594	(18,375)
Balance at end of period		366,534	412,293	366,534	412,293
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period		(23,126)	(10,504)	(24,719)	(372)
Balance at end of period		(23,125)	(18,747)	(23,125)	(18,747)
Unrealized gain on cash flow hedge:
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period		8,647	5,313	11,091	(246)
Other comprehensive income (loss) before reclassification		5,149	2,214	3,709	7,451
Amounts reclassified from accumulated other comprehensive income		(1,346)	146	(2,350)	468
Total other comprehensive income (loss), after tax		3,803	2,360	1,359	7,919
Balance at end of period		12,450	7,673	12,450	7,673
Unrealized Gains and (Losses) on Available-for-Sale Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period		(32,144)	(14,648)	(36,183)	1,091
Other comprehensive income (loss) before reclassification		(3,800)	(10,805)	239	(26,544)
Amounts reclassified from accumulated other comprehensive income		0	(14)	0	(14)
Total other comprehensive income (loss), after tax		(3,800)	(10,819)	239	(26,558)
Balance at end of period		(35,944)	(25,467)	(35,944)	(25,467)
Post-Retirement Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period		371	(1,169)	373	(1,217)
Other comprehensive income (loss) before reclassification	[1]	0	164	0	164
Amounts reclassified from accumulated other comprehensive income		(2)	52	(4)	100
Total other comprehensive income (loss), after tax		(2)	216	(4)	264
Balance at end of period		$ 369	$ (953)	$ 369	$ (953)

[1] Benefit arising from plan amendment approved in June 2022.