XML 26 R6.htm IDEA: XBRL DOCUMENT v3.20.4
CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Operating activities:      
Net loss $ (138,061) $ (84,486) $ (126,757)
Adjustments to reconcile net loss to net cash used in operating activities:      
Stock-based compensation expense 14,925 13,785 11,713
Non-cash interest expense 11,649 9,232 5,635
Depreciation and amortization 1,616 1,790 962
Loss on early extinguishment of debt 13,374   12,993
Deferred income tax (12,011) 0 (12,929)
Fair value settlement upon termination of cap call contract 838   354
Changes in operating assets and liabilities:      
Receivables 31,344 (12,367) (5,674)
Inventory (208) (1,059) 355
Prepaid expenses and other assets (3,816) (251) (498)
Accounts payable and accrued expenses (19,736) 13,283 10,109
Net cash used in operating activities (100,086) (60,073) (103,737)
Investing activities:      
Purchases of property and equipment (283) (334) (567)
Purchases of investments (133,194) (58,217) (68,782)
Proceeds from the sale and maturities of investments 66,446 55,150 94,500
Net cash (used in) provided by investing activities (67,031) (3,401) 25,151
Financing activities:      
Proceeds from issuance of convertible senior notes 225,030   210,000
Payments for debt issuance costs (6,785)   (6,800)
Proceeds from debt borrowings     44,550
Purchases of capped calls related to convertible senior notes (23,223)   (33,180)
Payments for repurchases of convertible senior notes (125,638)    
Repayment of debt     (132,077)
Payments on debt prepayment and extinguishment     (11,902)
Proceeds from termination of capped call contracts 7,549    
Proceeds from issuance of common stock, net 93,675 54,238  
Proceeds upon exercise of stock options and warrants 5,022 7,598 6,732
Release in restricted investments 99   4,681
Principal payments on finance lease liabilities (1,195) (1,139) (951)
Net cash provided by financing activities 174,534 60,697 81,053
Net increase (decrease) in cash and cash equivalents 7,417 (2,777) 2,467
Cash and cash equivalents at beginning of period 3,084 5,861 3,394
Cash and cash equivalents at end of period 10,501 3,084 5,861
Supplemental cash flow information      
Cash paid for interest 11,603 13,462 8,896
Property acquired under finance lease $ 216 $ 1,440 2,118
Conversion of accrued interest to debt     3,408
Fair value of warrants issued in connection with debt amendment     $ 1,424