Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities
Net loss	$ (7,675)	$ (15,582)
Adjustments required to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation of property and equipment	919	849
Amortization of intangible assets	3,657	3,619
Bad debt (income) expense	(26)	46
Mark-to-market (income) expense	(313)	27
Stock-based compensation expense	2,419	2,219
Change in unrealized gain during the period on short-term investments available for sale		7
Net changes in operating assets and liabilities:
(Increase) decrease in accounts receivable	(3,376)	641
Increase in prepaid expenses, other current assets and other long-term assets	(835)	(101)
Increase in accounts payable and accrued expenses	8,998	1,994
Increase in deferred rent and security deposits payable	119	139
(Decrease) increase in deferred revenue	(16)	356
Net cash provided by (used in) operating activities	3,871	(5,786)
Cash flows from investing activities
Purchase of property and equipment	(1,757)	(902)
Maturities of short-term investments		8,652
Change in restricted cash	621	36
Acquisition of InPlay		(1,800)
Acquisition of Transpera, Inc., net of cash acquired		15
Net cash (used in) provided by investing activities	(1,136)	6,001
Cash flows from financing activities
Net proceeds from common stock issuance	66,598
Repayment of amount outstanding under credit facility	(6,000)
Proceeds from the exercise of stock options	492	162
Net cash provided by financing activities	61,090	162
Net increase in cash and cash equivalents	63,825	377
Effect of exchange rate changes in cash and cash equivalents	(100)	(36)
Cash and cash equivalents at beginning of period	32,533	31,714
Cash and cash equivalents at end of period	$ 96,258	$ 32,055