Derivative Instruments and Hedging Activities - Schedule of Gross Amounts of Derivative Assets and Derivative Liabilities (Detail) (Not Designated as Hedging Instruments [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Not Designated as Hedging Instruments [Member]
Derivative Asset [Abstract]
Gross amounts recognized	$ 13,716		$ 14,012
Gross amounts offset	(283)		(314)
Net amounts presented in the Consolidated Balance Sheets	13,433		13,698
Gross amounts not offset	0	[1]	0	[1]
Net Amount	13,433		13,698
Derivative Liability [Abstract]
Gross amounts recognized	13,673		13,961
Gross amounts offset	(283)		(314)
Net amounts presented in the Consolidated Balance Sheets	13,390		13,647
Gross amounts not offset	11,157	[1]	12,611	[1]
Net Amount	$ 2,233		$ 1,036

[1] Amounts represent posted collateral.