Derivative Instruments and Hedging Activities - Income for Derivatives Not Designated as Hedging Instruments (Detail) (Not Designated as Hedging Instrument [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Income for derivatives not designated as hedging instruments	$ (1,147)	$ 715	$ (23)
Net Gain (Loss) on Mortgage Banking Activities [Member] | Interest Rate Locks with Customers [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Income for derivatives not designated as hedging instruments	(1,226)	467	549
Net Gain (Loss) on Mortgage Banking Activities [Member] | Forward Loan Sale Commitments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Income for derivatives not designated as hedging instruments	$ 79	$ 248	$ (572)