v3.8.0.1
Consolidated Statements of Cash Flows - USD ($)
$ in Thousands
 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Cash flows from operating activities    
Net loss $ (19,504) $ (29,647)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:    
Depreciation and amortization 2,371 2,665
Stock-based compensation 12,961 16,765
Other (45) 280
Changes in operating assets and liabilities:    
Accounts receivable, net 9,004 352
Inventories (577) (4,916)
Prepaid expenses and other current assets (1,575) 901
Other assets (262) (93)
Accounts payable (911) (1,956)
Accrued liabilities (329) (1,239)
Other liabilities 93 400
Deferred revenue 6,589 6,147
Net cash provided by (used in) operating activities 7,815 (10,341)
Cash flows from investing activities    
Purchases of property and equipment (510) (1,737)
Maturities of short-term investments 29,600 25,600
Purchases of short-term investments (36,189) (14,488)
Investment in privately held company 0 (1,500)
Net cash provided by (used in) investing activities (7,099) 7,875
Cash flows from financing activities    
Proceeds from exercise of vested stock options 723 815
Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options 2,390 2,890
Payment for shares withheld for tax withholdings on vesting of restricted stock units (1,070) (941)
Payment to repurchase common stock (3,030) (2,139)
Repayments of Long-term Capital Lease Obligations (126) 0
Net cash provided by (used in) financing activities (1,113) 625
Net decrease in cash and cash equivalents (397) (1,841)
Cash and cash equivalents at beginning of period 34,346 45,741
Cash and cash equivalents at end of period 33,949 43,900
Supplemental disclosure of cash flow information    
Income taxes paid 295 535
Interest paid 424 364
Supplemental disclosure of noncash investing and financing activities    
Unpaid property and equipment purchases $ 62 $ 1,529