Derivative Financial Instruments - Impact of Derivatives on Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 7,808	$ 15,314
Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Derivative Assets	7,808	15,314
Derivative Liabilities	(25,937)	(30,497)
Total net derivatives	(18,129)	(15,183)
Trading | Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Derivative Assets	0	83
Derivative Liabilities	(1,076)	(646)
Total net derivatives	(1,076)	(563)
Cash Flow | Designated as Hedging Instrument | Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Derivative Assets	0	0
Derivative Liabilities	(14,463)	(27,512)
Total net derivatives	(14,463)	(27,512)
Fair Value | Designated as Hedging Instrument | Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Derivative Assets	7,808	15,231
Derivative Liabilities	(10,398)	(2,339)
Total net derivatives	$ (2,590)	$ 12,892