Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Activities
Net income (loss)	$ 681,813	$ 575,667	$ (20,719)
Loss from discontinued operations	0	0	42,704
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Amortization and impairment of intangible assets	67,230	62,913	82,878
Depreciation and amortization of property and equipment	72,079	78,983	87,137
Amortization of debt discount and transaction costs	10,219	39,099	38,298
Amortization of deferred costs	44,829	38,144	0
Amortization of operating lease right-of-use assets	50,163
Stock-based compensation expense	278,892	203,619	165,120
Deferred income tax (benefit) expense	(244,933)	(13,156)	94,158
Effects of exchange rate changes on monetary assets and liabilities denominated in foreign currencies	2,631	7,950	(7,645)
Other non-cash items	10,630	11,872	11,924
Total adjustments to reconcile net income (loss) to net cash provided by operating activities	291,740	429,424	471,870
Changes in operating assets and liabilities, net of the effects of acquisitions:
Accounts receivable	(38,994)	18,703	(33,904)
Inventories	3,046	(8,239)	(2,545)
Prepaid expenses and other current assets	(7,129)	(7,855)	(18,327)
Other assets	(74,152)	(33,638)	2,116
Income taxes, net	(22,147)	(56,988)	318,795
Accounts payable	8,994	6,804	(7,238)
Accrued expenses and other current liabilities	(25,722)	36,967	34,886
Deferred revenues	(38,780)	69,499	174,426
Other liabilities	4,401	5,001	2,282
Total changes in operating assets and liabilities, net of the effects of acquisitions	(190,483)	30,254	470,491
Net cash provided by operating activities of continuing operations	783,070	1,035,345	964,346
Net cash used in operating activities of discontinued operations	0	0	(56,070)
Net cash provided by operating activities	783,070	1,035,345	908,276
Investing Activities
Purchases of available-for-sale investments	(20,003)	(466,687)	(1,155,659)
Proceeds from sales of available-for-sale investments	942,985	455,417	775,135
Proceeds from maturities of available-for-sale investments	178,070	468,145	466,900
Purchases of property and equipment	(63,454)	(69,354)	(80,901)
Cash paid for acquisitions, net of cash acquired	0	(248,929)	(60,449)
Cash paid for licensing agreements, patents and technology	(3,500)	(3,210)	(7,379)
Other	1,651	(3,202)	2,323
Net cash (used in) provided by investing activities of continuing operations	1,035,749	132,180	(60,030)
Net cash used in investing activities of discontinued operations	0	0	(3,891)
Net cash provided by (used in) investing activities	1,035,749	132,180	(63,921)
Financing Activities
Proceeds from issuance of common stock under stock-based compensation plans	0	164	2,114
Proceeds from revolving credit facility	200,000	0	165,000
Repayments on credit facility	(200,000)	0	(165,000)
Proceeds from 2027 notes, net of issuance costs	0	0	741,039
Repayment of acquired debt	0	(5,674)	(4,000)
Stock repurchases, net	(453,853)	(1,261,153)	(1,174,957)
Accelerated stock repurchase program	0	0	(150,000)
Cash paid for tax withholding on vested stock awards	(89,213)	(71,593)	(80,040)
Common stock cash dividends paid	(182,947)	(46,799)	0
Repayment on convertible debt	(1,164,497)	(272,986)	0
Transfer of cash to GoTo Business resulting from the separation	0	0	(28,523)
Net cash used in financing activities	(1,890,510)	(1,658,041)	(694,367)
Effect of exchange rate changes on cash and cash equivalents	(1,314)	(5,848)	8,186
Change in cash and cash equivalents	(73,005)	(496,364)	158,174
Cash and cash equivalents at beginning of period, including cash of discontinued operations of $120,861 in 2017	618,766	1,115,130	956,956
Cash and cash equivalents at end of period	$ 545,761	$ 618,766	$ 1,115,130