Accumulated Other Comprehensive Income - Summary of Changes in Accumulated Other Comprehensive Income (Loss) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (2,926)	$ 1,795	$ (1,062)
Net change in unrealized gain (loss)	(14,882)	(2,898)	4,814
Transfer of net unrealized loss from available for sale to held to maturity, net of cumulative tax effect	(5,919)
Reclassification of net gains realized and included in earnings	(316)	(4,324)	(485)
Amortization of unrealized net loss on securities	211
Income tax expense (benefit)	(7,317)	(2,501)	1,472
Ending balance	(16,515)	(2,926)	1,795
Cash Flow Hedge [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(4,455)
Net change in unrealized gain (loss)	3,694	(6,854)
Transfer of net unrealized loss from available for sale to held to maturity, net of cumulative tax effect
Reclassification of net gains realized and included in earnings
Amortization of unrealized net loss on securities
Income tax expense (benefit)	1,293	(2,399)
Ending balance	(2,054)	(4,455)
Transfers of Available for Sale Securities to Held to Maturity [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance
Net change in unrealized gain (loss)
Transfer of net unrealized loss from available for sale to held to maturity, net of cumulative tax effect	(5,919)
Reclassification of net gains realized and included in earnings
Amortization of unrealized net loss on securities	211
Income tax expense (benefit)	(1,998)
Ending balance	(3,710)
Available-for-sale securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	1,529	1,795	(1,062)
Net change in unrealized gain (loss)	(18,576)	3,956	4,814
Transfer of net unrealized loss from available for sale to held to maturity, net of cumulative tax effect
Reclassification of net gains realized and included in earnings	(316)	(4,324)	(485)
Amortization of unrealized net loss on securities
Income tax expense (benefit)	(6,612)	(102)	1,472
Ending balance	$ (10,751)	$ 1,529	$ 1,795