CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 34,800	$ 34,741
Net unrealized (losses) gains on investment securities available for sale:
Change in net unrealized losses	(258)	(189)
Net unrealized losses reclassified into net income	24	224
Net unrealized (losses) gains on investment securities available for sale	(234)	35
Net change in pension-related amounts:
Amortization of loss	219	246
Net change in pension-related amounts	219	246
Other comprehensive (loss) income	(15)	281
Income tax effect on:
Change in net unrealized losses on investment securities	65	49
Net unrealized losses reclassified into net income on investment securities	(6)	(58)
Pension-related amounts	(55)	(63)
Income tax benefit (provision) on other comprehensive (loss) income	4	(72)
Other comprehensive (loss) income, net of tax	(11)	209
Comprehensive income	$ 34,789	$ 34,950