Business Acquisition - Additional Information (Details) (USD $)	3 Months Ended								12 Months Ended					0 Months Ended	12 Months Ended					0 Months Ended	12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 General and administrative	Dec. 31, 2012 General and administrative	Apr. 05, 2012 Sonar Limited Employee	Dec. 31, 2013 Sonar Limited	Dec. 31, 2013 Sonar Limited Developed technology	Dec. 31, 2013 Sonar Limited Customer relationships	Dec. 31, 2013 Sonar Limited Non-compete agreements	Dec. 31, 2013 Sonar Limited Domains/trademarks/tradenames	Apr. 05, 2012 Sonar Limited Common Stock	Dec. 31, 2013 Sonar Limited Restricted stock awards	Dec. 31, 2012 Sonar Limited General and administrative
Business Acquisition [Line Items]
Business acquisition, cash paid														$ 12,500,000
Common stock issued for business acquisition (in shares)																				15,530	31,164
Fair value of common stock issued for business acquisition														300,000							700,000
Cash consideration and shares issued placed in escrow														1,800,000
Reasons for business acquisition, size of target client by number of employees														400
Identified intangible assets amortization period																4 years	4 years	2 years 6 months	2 years
Identified intangible assets combined weighted average useful life															3 years 9 months 18 days
Acquisition related costs												0	700,000									700,000
Net revenue attributable to Sonar	54,856,000	48,270,000	44,346,000	37,657,000	36,426,000	30,768,000	26,718,000	24,002,000	185,129,000	117,914,000	73,022,000
Net loss attributable to Sonar	$ 10,755,000	$ 11,054,000	$ 8,683,000	$ 9,934,000	$ 7,417,000	$ 7,627,000	$ 8,234,000	$ 8,112,000	$ 40,426,000	$ 31,390,000	$ 63,900,000
Award ratable vesting period																					2 years