CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019		Jun. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (93,908)		$ (60,941)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	48,771		44,610
Non-cash interest expense	8,870		17,300
Accretion of discount on investments	(1,510)		(41)
Stock-based compensation	82,590		75,214
Gain on sale of intangible assets	(15,000)		(20,000)
Deferred income taxes	(10,083)		(29,681)
Unrealized foreign exchange (gain) loss	799		(5,693)
Non-cash changes in the fair value of contingent consideration	4,891		1,828
Other	(3,603)		1,772
Changes in operating assets and liabilities:
Accounts receivable, net	(31,030)		(77,416)
Inventory	(33,119)		15,493
Other current assets	(4,989)		(2,037)
Other assets	(4,593)		(6,448)
Accounts payable and accrued liabilities	(37,571)		(32,989)
Other long-term liabilities	10,279		2,663
Net cash used in operating activities	(79,206)		(76,366)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property, plant and equipment	(61,387)		(52,682)
Maturities and sales of investments	423,477		311,969
Purchases of available-for-sale securities	(386,320)		(345,458)
Proceeds from sale of intangible asset	0		20,000
Purchase of intangible assets	(5,770)		0
Proceeds from sale of intangible asset	(808)		(841)
Net cash used in investing activities	(30,808)		(67,012)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from exercises of awards under equity incentive plans	19,013		44,926
Taxes paid related to net share settlement of equity awards	(36,900)		(28,614)
Payment of contingent acquisition consideration	(57,507)		(43,108)
Other	(1,347)		0
Net cash used in financing activities	(76,741)		(26,796)
Effect of exchange rate changes on cash	350		(443)
NET DECREASE IN CASH AND CASH EQUIVALENTS	(186,405)		(170,617)
Cash and cash equivalents:
Beginning of period	493,982	[1]	598,028
End of period	307,577		427,411
SUPPLEMENTAL CASH FLOW DISCLOSURES:
Cash paid for income taxes	3,933		14,858
Cash paid for interest	4,295		5,831
SUPPLEMENTAL CASH FLOW DISCLOSURES FOR NON CASH INVESTING AND FINANCING ACTIVITIES:
Decrease in accounts payable and accrued liabilities related to fixed assets	$ (3,467)		$ (7,734)

[1] December 31, 2018 balances were derived from the audited Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018, filed with the SEC on February 28, 2019.