Premises and Equipment - Summary of Premises and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Land	$ 105,435	$ 82,335
Leasehold improvements	229,919	219,152
Premises and equipment, gross	1,406,579	1,314,422
Less: accumulated depreciation and amortization	739,897	701,438
Premises and equipment, net	666,682	612,984
Owned Assets [Member]
Property, Plant and Equipment [Line Items]
Buildings	443,507	406,522
Furniture and equipment	614,591	586,429
Less: accumulated depreciation and amortization	732,315	686,372
Capital Leases [Member]
Property, Plant and Equipment [Line Items]
Buildings	1,108	1,131
Furniture and equipment	12,019	18,853
Less: accumulated depreciation and amortization	$ 7,582	$ 15,066