CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)
Net income	$ 14,985	$ 39,481	$ 79,786	$ 112,497
Other comprehensive income (loss):
Change in net unrealized loss during the period	(4,374)	(39,692)	(17,967)	(142,980)
Reclassification adjustment for net losses included in net loss on sale of securities and other assets			1,447
Accretion of net unrealized loss on securities transferred to held-to-maturity	788	1,112	2,341	2,111
Change in pension and other postretirement obligations:
Reclassification adjustment for expense included in other expense	(370)	(935)	(1,110)	(2,805)
Change in the net actuarial gain	518	997	1,553	2,992
Change in unrealized gain (loss) on derivatives:
Change in net unrealized (loss) gain during the period	(246)	5,387	(771)	14,548
Reclassification adjustment for expense included in interest expense	293	(546)	279	(569)
Other comprehensive loss before income taxes	(3,391)	(33,677)	(14,228)	(126,703)
Deferred tax benefit	(863)	(10,591)	(1,694)	(39,848)
Total other comprehensive loss, net of tax	(2,528)	(23,086)	(12,534)	(86,855)
Total comprehensive income	$ 12,457	$ 16,395	$ 67,252	$ 25,642