Accumulated Other Comprehensive Income or Loss and Earnings Per Share (Computation Of Basic And Diluted Earnings Per Common Share) (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Equity [Abstract]
Net income	$ 180,198	$ 127,391
Less: Preferred stock dividends	6,991	6,991
Net income applicable to common shares	$ 173,207	$ 120,400
Weighted average common shares outstanding (in shares)	60,950	57,196
Effect of dilutive potential common shares
Common stock equivalents (in shares)	873	862
Weighted average common shares and effect of dilutive potential common shares (in shares)	61,823	58,058
Net income per common share:
Basic (usd per share)	$ 2.84	$ 2.11
Diluted (usd per share)	$ 2.80	$ 2.07