Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income		$ 201,029	$ 144,538
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and other		8,362	5,697
Stock-based compensation		24,291	20,851
Deferred income taxes		(718)	(3,541)
Gain on investment in privately-held companies		(1,150)	0
Accretion of investment discounts		(2,069)	(30)
Changes in operating assets and liabilities:
Accounts receivable, net		60,531	40,007
Inventories		(82,596)	38,067
Prepaid expenses and other current assets		30,664	13,722
Other assets		1,214	(2,027)
Accounts payable		(2,391)	20,040
Accrued liabilities		(19,014)	(48,140)
Deferred revenue		(50,756)	(42,686)
Income taxes payable		2,040	3,478
Other liabilities		660	5,565
Net cash provided by operating activities		170,097	195,541
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from maturities of marketable securities		302,264	90,448
Purchases of marketable securities		(332,247)	(267,976)
Purchases of property and equipment		(5,237)	(6,336)
Net cash used in investing activities		(35,220)	(183,864)
CASH FLOWS FROM FINANCING ACTIVITIES:
Principal payments of lease financing obligations		0	(456)
Proceeds from issuance of common stock under equity plans		26,323	17,300
Tax withholding paid on behalf of employees for net share settlement		(1,850)	(1,536)
Net cash provided by financing activities		24,473	15,308
Effect of exchange rate changes		195	(14)
NET INCREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH		159,545	26,971
CASH, CASH EQUIVALENTS AND RESTRICTED CASH —Beginning of period		654,164	864,697
CASH, CASH EQUIVALENTS AND RESTRICTED CASH —End of period	[1]	813,709	891,668
SUPPLEMENTAL DISCLOSURES OF NON-CASH INVESTING AND FINANCING INFORMATION:
Right-of-use assets recognized upon the adoption of ASC 842	[2]	93,207	0
Right-of-use assets obtained in exchange for new operating lease liabilities		9,034	0
Property and equipment included in accounts payable and accrued liabilities		$ 1,055	$ 2,426

[1] See Note 4 of the accompanying notes for a reconciliation of the ending balance of cash, cash equivalents and restricted cash as shown in this condensed consolidated statements of cash flows.

[2] See Note 1 of the accompanying notes.