Derivative Financial Instruments - Summary of Fair Value of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Total derivative assets	$ 16,597	$ 17,701
Total derivative liabilities	21,749	23,574
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Total derivative assets	3,113	3,056
Total derivative liabilities	9,433	11,582
Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member]
Derivative [Line Items]
Total derivative assets	3,113	3,056
Total derivative liabilities	9,433	11,582
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Total derivative assets	13,484	14,645
Total derivative liabilities	12,316	11,992
Not Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member]
Derivative [Line Items]
Total derivative assets	11,913	11,903
Total derivative liabilities	11,994	11,992
Not Designated as Hedging Instrument [Member] | Mortgage Contracts [Member]
Derivative [Line Items]
Total derivative assets	1,571	$ 2,742
Total derivative liabilities	$ 322