Valuation and Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at the beginning of the year	$ 202	$ 36	$ 96
Charged to costs and expenses	56	237	33
Charged to other accounts	0	0	0
Write-offs	(58)	(71)	(93)
Balance at the end of the year	$ 200	$ 202	$ 36