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v3.8.0.1

Statements of Cash Flows - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Cash flows from operating activities |  |  |
Net income (loss) | $ (48,925) | $ 23,625 | $ (17,592)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities |  |  |
Depreciation and amortization | 2,030 | 1,466 | 1,113
Amortization of premium on marketable securities | 2,845 | 2,037 | 1,096
Stock-based compensation | 13,651 | 7,848 | 4,869
Abandonment of capitalized intangible assets | 396 | 356 | 296
Loss (gain) on disposal of assets | 83 |  | (9)
Gain on sale of marketable securities available-for-sale |  | (5) | (5)
Changes in operating assets and liabilities: |  |  |
Accounts receivable | 7,474 | (8,572) | 2,922
Interest receivable | (293) | (530) | (898)
Prepaid expenses and other current assets | (2,705) | (1,700) | (1,068)
Income tax receivable | (1,524) |  |
Other assets | (161) | (40) | (3)
Accounts payable | 2,989 | (2,520) | 4,710
Accrued expenses | (1,212) | 3,058 | 1,425
Deferred rent | 589 | (89) | 572
Income tax payable | 91 | 65 |
Deferred revenue | (9,011) | 69,618 | 29,238
Net cash provided by (used in) operating activities | (33,683) | 94,617 | 26,666
Cash flows from investing activities |  |  |
Proceeds from sale and maturities of marketable securities | 115,757 | 105,505 | 34,358
Proceeds from sale of property and equipment |  |  | 9
Purchase of marketable securities | (76,529) | (316,149) | (215,798)
Purchase of intangible assets | (1,967) | (1,502) | (1,745)
Purchase of property and equipment | (5,311) | (1,507) | (1,930)
Net cash provided by (used in) investing activities | 31,950 | (213,653) | (185,106)
Cash flows from financing activities |  |  |
Proceeds from issuance of common stock upon exercise of stock awards | 2,797 | 1,160 | 554
Proceeds from issuance of common stock under the Employee Stock Purchase Plan | 936 | 545 | 623
Proceeds from issuance of common stock |  | 126,546 | 122,906
Common stock issuance cost |  | (7,277) | (7,702)
Net cash provided by financing activities | 3,733 | 120,974 | 116,381
Net increase (decrease) in cash and cash equivalents | 2,000 | 1,938 | (42,059)
Cash and cash equivalents, beginning of period | 14,528 | 12,590 | 54,649
Cash and cash equivalents, end of period | 16,528 | 14,528 | 12,590
Cash paid during the period for: |  |  |
Interest | 13 | 21 | 13
Taxes | 969 | 936 | 1
Supplemental disclosures of non-cash investing activities |  |  |
Unrealized loss on marketable securities, net of tax | $ 367 | $ 925 | $ 516

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- Definition The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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- Definition Amount of unrealized gain (loss) on investments in debt and equity securities classified as available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 + Details
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4K -URI http://asc.fasb.org/extlink&oid=84234705&loc=SL4591552-111686 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4569616-111683 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84161450&loc=SL4573702-111684 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4J -URI http://asc.fasb.org/extlink&oid=84234705&loc=SL4591551-111686 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=84161450&loc=SL4573702-111684 + Details
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