Total Income Tax (Benefit) Expense (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Current taxes
Federal taxes									$ 57	$ (464)	$ (811)
State taxes									640	329	72
Foreign taxes									506	164	310
Current taxes									1,203	29	(429)
Deferred taxes
Federal taxes									(376)	56	807
State taxes									537	(4,372)	(15)
Foreign taxes									(28)		(1)
Deferred taxes									133	(4,316)	791
Income tax (benefit) expense	$ 334	$ 70	$ 392	$ 540	$ (4,926)	$ (1,338)	$ (963)	$ 2,940	$ 1,336	$ (4,287)	$ 362