CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Cash flows from operating activities:      
Net loss $ (21,411) $ (27,698) $ (15,834)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:      
Depreciation expense 4,458 3,114 3,098
Amortization of intangible assets 4,825 5,094 3,485
Provision for doubtful accounts and service remediation reserves 999 595 48
Stock-based compensation 10,395 13,655 12,241
Stock-based compensation related to acquisition 0 0 42
Patent settlement expense 0 0 701
Release of valuation allowance 0 (350) (3,217)
Loss (gain) on disposal of property and equipment 3 (2) (6)
Impairment of investments 0 0 375
Amortization of convertible notes issuance cost 485 402 355
Gain on extinguishment of convertible notes 0 0 (915)
Net amortization on investments 79 358 510
Induced Conversion of Convertible Debt Expense 4,776 0 0
Acquisition-related contingent consideration 0 (1,612) 0
Changes in operating assets and liabilities:      
Accounts receivable (7,648) (1,112) (36)
Prepaid and other current assets 486 (820) 1,775
Other assets (1,276) 662 (2,667)
Accounts payable (1,702) 914 1,300
Accrued expenses 106 (1,106) (2,763)
Accrued payroll and related expenses 1,971 987 1,422
Accrued restructuring (503) 443 146
Deferred revenue 17,469 4,576 62
Deferred income taxes 237 195 24
Net cash (used in) provided by operating activities 13,749 (1,705) 146
Cash flows from investing activities:      
Purchases of investments (7,434) (16,536) (52,886)
Proceeds from maturities and sale of investments 12,250 38,841 35,511
Purchases of property and equipment (1,704) (6,692) (2,002)
Proceeds from disposal of property and equipment 0 2 6
Purchases of intangible assets (638) (6,196) (1,522)
Acquisitions, net of cash acquired 0 (7,715) (19,482)
Net cash provided by (used in) investing activities 2,474 1,704 (40,375)
Cash flows from financing activities:      
Proceeds from issuance of common stock 6,629 5,225 5,556
Repurchases of common stock 0 0 (14,430)
Repurchase of common stock from employees for payment of taxes on vesting of restricted stock units (1,297) (2,346) (1,402)
Payment of consideration related to acquisitions (2,903) (2,660) (1,210)
Proceeds from issuance of convertible notes, net of issuance costs 0 0 76,854
Repurchase of convertible notes 0 0 (19,448)
Payment on debt conversion (4,374) 0 0
Repayment of debt assumed through acquisition 0 (30) 0
Payment of principal under capital leases (2,319) (1,193) (1,170)
Net cash (used in) provided by financing activities (4,264) (1,004) 44,750
Effect of exchange rates on cash and cash equivalents (64) 22 32
Net (decrease) increase in cash and cash equivalents 11,895 (983) 4,553
Cash and cash equivalents at beginning of period 16,400 17,383 12,830
Cash and cash equivalents at end of period 28,295 16,400 17,383
Supplemental disclosures of cash flow information:      
Cash paid for interest on convertible debt 2,604 2,813 1,713
Cash paid for interest on capital leases 100 101 175
Income Taxes Paid, Net 162 0 0
Conversion of debt to equity 44,383    
Debt Conversion, Converted Instrument, Amount 45,018 0 0
Reclassification of deferred debt issuance cost to additional paid-in capital 1,037 0 0
Common stock issued as a premium of debt conversion 402 0 0
Fixed assets acquired under capital lease $ 3,851 $ 0 $ 0