Premises and Equipment (Premises and Equipment) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Land	$ 111,925	$ 102,334
Buildings	365,051	240,430
Furniture and equipment	136,983	102,885
Leasehold improvements	64,446	60,902
Construction in progress	81,991	118,367
Premises and equipment, Gross	760,396	624,918
Less accumulated depreciation and amortization	(201,272)	(182,748)
Total premises and equipment, net	$ 559,124	$ 442,170