Premises and Equipment (Schedule of Premises and Equipment) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Premises and equipment	$ 141,281	$ 136,884
Less: accumulated depreciation and amortization	(38,178)	(30,543)
Property, Plant and Equipment, Net, Total	103,103	106,341
Land [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment	29,991	30,106
Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment	71,908	69,046
Equipment [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment	$ 39,382	$ 37,732