Maturities of Marketable Securities (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Schedule Of Investments [Line Items]
Less than 1 year	$ 17,387	$ 20,658
Due in 1 to 2 years	2,010	2,008
Due in 2 to 5 years
Due after 5 years	1,700	1,801
Total	$ 21,097	$ 24,467