Stock Based Compensation - Summary of Stock Based Compensation Expense (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock based compensation	$ 3,045	$ 1,224	$ 1,530
Service, rental and maintenance [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock based compensation	54	25	23
Selling and marketing [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock based compensation	70	72	65
General and administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock based compensation	$ 2,921	$ 1,127	$ 1,442