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v3.19.1

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018
Cash flows from operating activities |  |
Net loss | $ (45,017) | $ (49,536)
Adjustments to reconcile net loss to net cash used in operating activities: |  |
Depreciation and amortization expense | 2,903 | 1,338
Stock-based compensation | 3,799 | 3,432
Changes in operating assets and liabilities: |  |
Accounts receivable | 23,468 | 6,361
Prepaid expenses | (1,902) | (177)
Other assets | (2,079) | 40
Accounts payable and other liabilities | (2,531) | 7,815
Accrued expenses | (4,297) | 1,477
Lease exit liability | 0 | (298)
Deferred revenue | (5,430) | (1,435)
Lease liabilities | 1,086 | 0
Deferred rent | 0 | (312)
Net cash used in operating activities | (30,000) | (31,295)
Cash flows from investing activities |  |
Purchases of marketable securities | (81,597) | (24,452)
Proceeds from sale and maturities of marketable securities | 12,780 | 58,358
Purchases of property and equipment | (1,675) | (14,519)
Net cash provided by (used in) investing activities | (70,492) | 19,387
Cash flows from financing activities |  |
Proceeds from issuance of common stock, net of offering costs | 118,657 | 0
Proceeds from stock option exercises | 348 | 629
Net cash provided by financing activities | 119,005 | 629
Net change in cash and cash equivalents | 18,513 | (11,279)
Cash and cash equivalents at beginning of period | 220,128 | 211,727
Cash and cash equivalents at end of period | 238,641 | 200,448
Supplemental Cash Flow Information [Abstract] |  |
Right-of-use assets modified in exchange for operating lease obligations | $ 1,988 | $ 0

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