Earnings Per Common Share - Computations of Diluted Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Earnings Per Share [Abstract]
Net income available to common equity	$ 842,094	$ 192,581	$ 1,518,777	$ 532,990
Less: Income attributable to unvested stock-based compensation awards	(1,570)	(345)	(2,725)	(1,074)
Net income available to common shareholders	$ 840,524	$ 192,236	$ 1,516,052	$ 531,916
Adjusted weighted-average shares outstanding:
Common shares outstanding (including common stock issuable) and unvested stock-based compensation awards	166,152	177,682	167,076	153,612
Less: Unvested stock-based compensation awards	(310)	(315)	(294)	(322)
Plus: Incremental shares from assumed conversion of stock-based compensation awards	478	910	577	691
Adjusted weighted-average shares outstanding	166,320	178,277	167,359	153,981
Diluted earnings per common share	$ 5.05	$ 1.08	$ 9.06	$ 3.45