Income Taxes - Components of Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current
Federal	$ 359,668	$ 408,428	$ 363,043
State and local	132,696	113,706	94,714
Total current	492,364	522,134	457,757
Deferred
Federal	40,769	(12,780)	367,308
State and local	16,779	28,637	33,482
Total deferred	57,548	15,857	400,790
Amortization of investments in qualified affordable housing projects	68,200	52,169	57,009
Income taxes	$ 618,112	$ 590,160	$ 915,556