Fair Value Measurements - Fair Values and Unrealized Losses on Securities Available-for-Sale (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Less than Twelve Months, Estimated fair value	$ 2,616	$ 15,683
Less than Twelve Months, Gross unrealized losses	(8)	(19)
Twelve Months or More, Estimated fair value
Twelve Months or More, Gross unrealized losses
Estimated fair value, Total	2,616	15,683
Gross unrealized losses, Total	(8)	(19)
Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than Twelve Months, Estimated fair value	552	4,955
Less than Twelve Months, Gross unrealized losses	(3)	(6)
Twelve Months or More, Estimated fair value
Twelve Months or More, Gross unrealized losses
Estimated fair value, Total	552	4,955
Gross unrealized losses, Total	(3)	(6)
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than Twelve Months, Estimated fair value	2,064	10,728
Less than Twelve Months, Gross unrealized losses	(5)	(13)
Twelve Months or More, Estimated fair value
Twelve Months or More, Gross unrealized losses
Estimated fair value, Total	2,064	10,728
Gross unrealized losses, Total	$ (5)	$ (13)