Income Tax Expense (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Line Items]
Federal - current	$ (53,273)	$ 207,864	$ 205,985
State and local - current	(295)	53,654	40,417
Total current	(53,568)	261,518	246,402
Federal - deferred	468	23,814	20,734
State and local - deferred	(31,757)	2,337	4,443
Total deferred	(31,289)	26,151	25,177
Income tax (benefit) expense	(84,857)	287,669	271,579
Employee stock plans	(2,486)	(3,225)	(1,692)
Adoption of ASU No. 2014-01		1,303
Securities available-for-sale	131	1,851	(8,343)
Pension liability adjustments	(1,161)	(14,992)	20,116
Non-credit portion of OTTI losses	44	142	5,028
Total income taxes	$ (88,329)	$ 272,748	$ 286,688