CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net income (loss)	$ 205,095	$ 134,258	$ (19,425)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	96,870	101,590	103,821
Deferred income taxes	14,154	(26,697)	(2,150)
Share-based compensation	112,118	71,342	68,864
Gains on short-term investments, net	(14,963)	(5,278)	(3,460)
Gain on investments in privately-held companies	(9,569)	0	0
Impairment charges and loss on disposal of property and equipment	3,213	4,754	12,019
Changes in assets and liabilities, net of effect of acquisitions:
Accounts receivable, net	(79,248)	3,588	(12,175)
Inventories	1,297	(43,301)	(887)
Prepaid expenses and other assets	17,281	(2,650)	(681)
Accounts payable	33,812	10,486	170
Accrued liabilities and other liabilities	44,730	16,765	15,216
Net cash provided by operating activities	424,790	264,857	161,312
Cash flows from investing activities:
Purchase of severance-related insurance policies	0	(1,203)	(1,312)
Purchase of short-term investments	(890,545)	(395,560)	(188,745)
Proceeds from sales and maturities of short-term investments	490,900	230,629	252,211
Purchase of property and equipment, net of proceeds from sales	(37,791)	(33,099)	(41,376)
Purchase of intangible assets	(4,920)	(6,535)	(2,843)
Proceeds from sale of investments in privately-held companies	16,887	0	0
Purchase of investments in privately-held companies	(8,057)	(12,500)	(15,021)
Acquisitions, net of cash acquired	0	(7,379)	(872)
Net cash provided by (used in) investing activities	(433,526)	(225,647)	2,042
Cash flows from financing activities:
Principal payments on term debt	0	(74,000)	(172,000)
Principal payments on intangible assets obligations	(10,378)	(8,426)	(7,369)
Proceeds from issuances of ordinary shares through employee equity incentive plans	32,043	37,368	29,733
Net cash provided by (used in) financing activities	21,665	(45,058)	(149,636)
Net increase (decrease) in cash, cash equivalents, and restricted cash	12,929	(5,848)	13,718
Cash, cash equivalents, and restricted cash at beginning of period	64,650	70,498	56,780
Cash, cash equivalents, and restricted cash at end of period	77,579	64,650	70,498
Supplemental disclosures of cash flow information
Interest paid	0	577	5,384
Income taxes paid	2,464	2,174	1,218
Supplemental disclosure of non-cash investing and financing activities
Intangible assets financed with debt	28,594	2,585	12,981
Unpaid property and equipment	2,835	1,537	3,962
Transfer from inventory to property and equipment	$ 5,054	$ 3,577	$ 1,753