Unaudited Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (63,319)	$ 58,608	$ 19,199	$ 151,182
Unrealized gains (losses) on investment securities:
Unrealized holding gains (losses) arising during period	(6,594)	(47,937)	(18,887)	4,142
Unrealized gains (losses) on securities with credit loss recognized in earnings	(2,927)	(4,764)	(5,401)	12,957
Amounts reclassified into net income (loss):
Net realized (gains) losses on disposals and losses on intent-to-sell available-for-sale securities	33	7,413	(28)	12,235
Credit loss (benefit) expense	975	(683)	3,068	(8,210)
Total unrealized gains (losses) on investment securities	(8,513)	(45,971)	(21,248)	21,124
Defined benefit pension and post-retirement plans:
Amounts reclassified into net income (loss): Net actuarial loss	764	598	1,528	1,196
Total defined benefit pension and post-retirement plans	764	598	1,528	1,196
Other comprehensive income (loss)	(7,749)	(45,373)	(19,720)	22,320
Comprehensive income (loss)	$ (71,068)	$ 13,235	$ (521)	$ 173,502