Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Accounts receivable, allowance	$ 2,203	$ 2,250
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	160,000,000	160,000,000
Common stock, shares issued	45,398,523	18,914,616
Common stock, shares outstanding	44,442,494	17,158,904
Preferred stock, Par value	$ 0.001	$ 0.001
Preferred stock, authorized Series A-3 convertible preferred stock	0	290,277
Preferred stock, Series A-3 convertible preferred stock issued	0	290,277
Preferred stock, Series A-3 convertible preferred stock outstanding	0	290,277
Convertible Redeemable Preferred Stock
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, authorized	0	5,000,000
Series A-1 convertible redeemable preferred stock
Preferred stock, issued	0	2,054,935
Preferred stock, outstanding	0	2,054,935
Series A-2 convertible redeemable preferred stock
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, authorized	0	945,114
Preferred stock, issued	0	384,804
Preferred stock, outstanding	0	384,804