Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]
Contractual obligations, repayment term	36 months
Total contingent obligations due if contractual performance targets are not achieved	$ 1.4
Total contingent obligations due in 2015 if contractual performance targets are not achieved	0.9
Total contingent obligations due in 2016 if contractual performance targets are not achieved	0.2
Loss Contingency Possible Range Of Loss Maximum Year Three	0.3
Deferred revenue related to outstanding contractual performance targets	$ 0.9
Audit reimbursement period (in years), maximum	7 years