Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]
Total shareholders’ equity at beginning of period at Dec. 31, 2021	$ 4,439,555	$ 145,452	$ 642	$ 1,009,921	$ 2,956,966	$ 347,318	$ (20,744)
Net income	99,102				99,102
Other comprehensive income (loss)	(719,108)					(719,108)
Stock option exercises/stock unit conversions (50,387 shares YTD in 2023 and 115,430 shares YTD in 2022)	5,739				(3,314)		9,053
Stock compensation expense recognized in earnings	2,112			2,112
Purchase of treasury stock (9,183 shares YTD in 2023 and 7,459 shares YTD in 2022)	(996)						(996)
Cash dividends – preferred stock (approximately $11.13 per share which is equivalent to approximately $0.28 per depository share YTD in 2023 and 2022, respectively)	(1,669)				(1,669)
Cash dividends – common stock ($0.87 per share YTD in 2023 and $0.75 per share YTD in 2022)	(48,443)				(48,443)
Total shareholders’ equity at end of period at Mar. 31, 2022	3,776,292	145,452	642	1,012,033	3,002,642	(371,790)	(12,687)
Total shareholders’ equity at beginning of period at Dec. 31, 2022	3,137,228	145,452	643	1,029,756	3,309,671	(1,348,294)	0
Net income	177,653				177,653
Other comprehensive income (loss)	206,156					206,156
Stock option exercises/stock unit conversions (50,387 shares YTD in 2023 and 115,430 shares YTD in 2022)	1,500		1	1,463	(28)		64
Stock compensation expense recognized in earnings	4,742			4,742
Purchase of treasury stock (9,183 shares YTD in 2023 and 7,459 shares YTD in 2022)	(1,173)						(1,173)
Cash dividends – preferred stock (approximately $11.13 per share which is equivalent to approximately $0.28 per depository share YTD in 2023 and 2022, respectively)	(1,669)				(1,669)
Cash dividends – common stock ($0.87 per share YTD in 2023 and $0.75 per share YTD in 2022)	(56,636)				(56,636)
Total shareholders’ equity at end of period at Mar. 31, 2023	$ 3,467,801	$ 145,452	$ 644	$ 1,035,961	$ 3,428,991	$ (1,142,138)	$ (1,109)