Condensed Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Operating Activities
Net income	$ 136,450	$ 204,361
Loss (income) from discontinued operations	42,704	(24,818)
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and other	97,403	112,465
Stock-based compensation expense	75,487	74,428
Excess tax benefit from stock-based compensation	0	(10,308)
Deferred income tax expense (benefit)	56,584	(9,508)
Effects of exchange rate changes on monetary assets and liabilities denominated in foreign currencies	(6,049)	(2,242)
Other non-cash items	7,812	2,801
Total adjustments to reconcile net income to net cash provided by operating activities	231,237	167,636
Changes in operating assets and liabilities, net of the effects of acquisitions:
Accounts receivable	140,471	162,958
Inventories	(1,398)	(1,463)
Prepaid expenses and other current assets	(5,957)	(13,672)
Other assets	(9,597)	2,597
Income taxes, net	(73,567)	45,392
Accounts payable	(9,272)	(24,532)
Accrued expenses and other current liabilities	(20,536)	13,368
Deferred revenues	26,084	(28,052)
Other liabilities	(790)	(2,525)
Total changes in operating assets and liabilities, net of the effects of acquisitions	45,438	154,071
Net cash provided by operating activities of continuing operations	455,829	501,250
Net cash (used in) provided by operating activities of discontinued operations	(56,070)	67,077
Net cash provided by operating activities	399,759	568,327
Investing Activities
Purchases of available-for-sale investments	(590,004)	(907,498)
Proceeds from sales of available-for-sale investments	562,098	446,932
Proceeds from maturities of available-for-sale investments	179,330	322,100
Purchases of property and equipment	(38,650)	(48,687)
Cash paid for acquisitions, net of cash acquired	(60,449)	0
Cash paid for licensing agreements and technology	(5,155)	(24,577)
Other	987	544
Net cash provided by (used in) investing activities of continuing operations	48,157	(211,186)
Net cash used for investing activities of discontinued operations	(3,891)	(28,249)
Net cash provided by (used in) investing activities	44,266	(239,435)
Financing Activities
Proceeds from issuance of common stock under stock-based compensation plans	1,490	30,559
Proceeds from credit facility	125,000	0
Repayment of credit facility	(95,000)	0
Repayment of acquired debt	(4,000)	0
Excess tax benefit from stock-based compensation	0	10,308
Stock repurchases, net	(500,000)	(28,689)
Cash paid for tax withholding on vested stock awards	(60,547)	(43,842)
Transfer of cash to GoTo Business resulting from the separation	(28,523)	0
Net cash used in financing activities	(561,580)	(31,664)
Effect of exchange rate changes on cash and cash equivalents	5,370	486
Change in cash and cash equivalents	(112,185)	297,714
Cash and cash equivalents at beginning of period, including cash of discontinued operations of $120,861 and $57,762, respectively	956,956	368,518
Cash and cash equivalents at end of period	844,771	666,232
Less cash of discontinued operations	0	(71,126)
Cash and cash equivalents at end of period	$ 844,771	$ 595,106