Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (USD $) In Thousands	Total	Series A Convertible preferred stock	Series A-2 Convertible preferred stock	Series B Convertible preferred stock	Series C Convertible preferred stock	Total Convertible Preferred Stock	Common Stock	Additional Paid-in Capital	Treasury Stock	Note Receivable from Stockholder	Accumulated Deficit	Non-controlling Interests
Balance at Dec. 31, 2010	$ (49,640)	$ 22,263	$ 6,868	$ 13,948	$ 79,890	$ 122,969			$ (4,575)	$ (103)	$ (45,159)	$ 197
Balance (in shares) at Dec. 31, 2010		5,053	1,105	3,433	10,983		5,835
Increase (Decrease) in Stockholders' Equity
Accretion of convertible preferred stock	(1,633)	258	82	176	1,117	1,633					(1,633)
Issuance of common stock upon conversion of preferred stock	124,602	(22,521)	(6,950)	(14,124)	(81,007)	(124,602)	2	124,600
Issuance of common stock upon conversion of preferred stock (in shares)		(5,053)	(1,105)	(3,433)	(10,983)		22,846
Issuance of common stock upon initial public offering	48,297						1	48,296
Issuance of common stock upon initial public offering (in shares)							3,847
Issuance of common stock upon exercise and conversion of preferred stock warrants	271							271
Issuance of common stock upon exercise and conversion of preferred stock warrants (in shares)							20
Issuance of common stock upon exercise of common stock warrants (in shares)							21
Issuance of common stock upon exercise of stock options	602							602
Issuance of common stock upon exercise of stock options (in shares)							600
Offering costs	(2,534)							(2,534)
Stock-based compensation expense	2,275							2,275
Retirement of treasury stock	(4,575)							(4,575)	4,575
Forgiveness of note receivable from stockholder	103									103
Non-controlling interests	(441)											(441)
Net income	4,778										4,358	420
Balance at Sep. 30, 2011	$ 126,680	$ 0	$ 0	$ 0	$ 0	$ 0	$ 3	$ 168,935	$ 0	$ 0	$ (42,434)	$ 176
Balance (in shares) at Sep. 30, 2011							33,169