Derivative Instruments and Hedging Activities - Amount of Gain or Loss Recognized in Income on Derivatives (Detail) (Not Designated as Hedging Instruments [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivatives Gain (Loss)	$ 124	$ 88	$ 95	$ (243)
Interest Rate Swap Contracts-Commercial Loans [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivatives Gain (Loss)	(11)	(27)	(19)	(156)
Interest Rate Lock Commitments - Mortgage Loans [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivatives Gain (Loss)	199	(266)	207	(492)
Forward Sale Contracts-Mortgage Loans [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivatives Gain (Loss)	$ (64)	$ 381	$ (93)	$ 405