Property and Equipment - Property and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Property Plant And Equipment [Line Items]
Total costs	$ 20,450	$ 19,035
Less accumulated depreciation and amortization	(10,158)	(9,007)
Property and equipment, net	10,292	10,028
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Total costs	1,281	1,284
Computer Software and Equipment
Property Plant And Equipment [Line Items]
Total costs	18,455	17,036
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total costs	$ 714	$ 715