Segment Information and Concentrations of Risk - Schedule of Geographic Concentration of Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets by Geographic Concentration, Total	$ 111,465	$ 161,531
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets by Geographic Concentration, Total	108,932	157,661
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets by Geographic Concentration, Total	808	2,836
Europe, Latin America and Asia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Assets by Geographic Concentration, Total	$ 1,725	$ 1,034