CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net change in unrealized gains (losses), tax expense (benefit)	$ 20,085	$ (167,261)	$ (29,523)
Reclassification adjustment for net gains, tax expense	0	0	80
Amortization of unrealized gains (losses) on securities reclassified to held-to-maturity, tax (benefit) expense	(5,361)	(34,319)	(32)
Change in unfunded pension liability related to unrealized (loss) gain , prior service cost, tax expense (benefit)	1	(5)	50
Net change in cash flow hedge, tax expense	504	0	0
Amortization of unrealized gain on terminated cash flow hedges, tax benefit	(34)	51	119
Equity method investment tax (benefit) expense	(27)	$ 67	$ 114
Fannie Mae (FNMA) mortgage-backed securities (MBS)
Amortization of unrealized gains (losses) on securities reclassified to held-to-maturity, tax (benefit) expense	(119,800)
Securities transferred to held-to-maturity from available-for-sale, book value	$ 1,100,000