Earnings Per Common Share (Earnings Per Share Basic And Diluted) (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Earnings Per Share Reconciliation [Abstract]
Net income	$ 408,864	$ 220,621	$ 382,723
Less: Preferred stock dividends	7,875	7,875	7,875
Net income available to common shareholders, basic	400,989	212,746	374,848
Net income available to common shareholders, diluted	400,989	212,746	374,848
Less: Earnings applicable to participating securities, basic	2,302	1,272	1,863
Less: Earnings applicable to participating securities, diluted	2,302	1,272	1,863
Earnings applicable to common shareholders	398,687	211,474	372,985
Earnings applicable to common shareholders, diluted	$ 398,687	$ 211,474	$ 372,985
Earnings per common share:
Earnings per common share, Basic (in dollars per share)	$ 4.43	$ 2.35	$ 4.07
Earnings per common share, Diluted (in dollars per share)	$ 4.42	$ 2.35	$ 4.06
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Weighted-average common shares outstanding - basic	89,983	89,967	91,559
Stock options and restricted stock (in shares)	223	184	323
Weighted Average Number of Shares Outstanding, Diluted	90,206	90,151	91,882