Securities - Information Pertaining to Security Sales (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Investments, Debt and Equity Securities [Abstract]
Proceeds	$ 9,698	$ 0	$ 38,826	$ 33,672
Gross Gains	41	0	328	822
Gross Losses	$ 0	$ 0	$ (83)	$ (494)