Derivative Instruments and Hedging Activities - Fair Value of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative assets	$ 0	$ 192
Fair value, derivative liabilities	13,932	9,703
Designated as Hedging Instrument | Other assets
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative assets	0	0
Designated as Hedging Instrument | Other assets | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative assets	0	0
Designated as Hedging Instrument | Other liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative liabilities	4,477	1,945
Designated as Hedging Instrument | Other liabilities | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative liabilities	4,477	1,945
Not Designated as Hedging Instrument | Other assets
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative assets	9,295	7,552
Not Designated as Hedging Instrument | Other assets | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative assets	9,088	7,332
Not Designated as Hedging Instrument | Other assets | Credit contracts
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative assets	162	177
Not Designated as Hedging Instrument | Other assets | Residential mortgage loan commitments
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative assets	45	43
Not Designated as Hedging Instrument | Other liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative liabilities	9,455	7,771
Not Designated as Hedging Instrument | Other liabilities | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative liabilities	9,455	7,771
Not Designated as Hedging Instrument | Other liabilities | Credit contracts
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative liabilities	0	0
Not Designated as Hedging Instrument | Other liabilities | Residential mortgage loan commitments
Derivative Instruments, Gain (Loss) [Line Items]
Fair value, derivative liabilities	$ 0	$ 0