Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cash flows from operating activities
Net loss	$ (3,753)	$ (3,973)
Adjustments to reconcile net loss to net cash and cash equivalents used in operating activities:
Stock-based compensation expense	1,657	1,084
Non-cash change in fair value of Series B warrant prior to conversion		957
Bad debt expense	489	311
Depreciation and amortization	941	440
Amortization of deferred financing fees	7	7
Changes in assets and liabilities:
Accounts receivable	4,709	(1,808)
Prepaid expenses and other current assets	276	(143)
Other assets	46	(205)
Accounts payable and accrued expenses	643	(557)
Accrued cost of revenue	(4,893)	(884)
Accrued payroll and payroll related expenses	(2,233)	(1,843)
Other long-term liabilities	35	7
Deferred revenue	98	(86)
Net cash and cash equivalents used in operating activities	(1,978)	(6,693)
Cash flows from investing activities
Purchases of property and equipment	(1,840)	(588)
Net cash and cash equivalents used in investing activities	(1,840)	(588)
Cash flows from financing activities
Payment of deferred offering costs		(345)
Proceeds from exercises of stock options	202	52
Withholdings for vesting of restricted stock units	(261)
Net cash and cash equivalents used in financing activities	(59)	(293)
Effect of exchange rates on cash and cash equivalents	(66)	5
Net decrease in cash and cash equivalents	(3,943)	(7,569)
Cash and cash equivalents, beginning of the period	137,439	16,707
Cash and cash equivalents, end of the period	133,496	9,138
Supplemental disclosure of noncash investing and financing activities
Accretion of dividends on redeemable convertible preferred stock		1,328
Accretion of issuance costs on redeemable convertible preferred stock		$ 6