UNAUDITED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
OPERATING ACTIVITIES:
Net income	$ 955,062	$ 850,359
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	65,157	46,695
Amortization	85,426	85,981
Provision for uncollectible accounts, net	16,117	13,233
Deferred income tax benefit	(79,863)	(41,577)
Stock-based compensation expense and other stock-based payments	121,016	115,269
Amortization of debt issuance costs	3,744	4,218
Amortization of debt discount	34,180	33,211
Impairment of cost-method investments	63,208	0
Changes in assets and liabilities:
Accounts receivable	(344,147)	(287,940)
Prepaid expenses and other current assets	(286,976)	(300,482)
Accounts payable, accrued expenses and other current liabilities	687,973	405,818
Other	(10,563)	(13,426)
Net cash provided by operating activities	1,310,334	911,359
INVESTING ACTIVITIES:
Purchase of investments	(2,701,662)	(4,686,507)
Proceeds from sale of investments	2,176,868	2,231,926
Additions to property and equipment	(113,699)	(84,351)
Acquisitions and other investments, net of cash acquired	(795)	(45,937)
Proceeds from foreign currency contracts	0	453,818
Payments on foreign currency contracts	0	(448,640)
Change in restricted cash	(6)	(225)
Net cash used in investing activities	(639,294)	(2,579,916)
FINANCING ACTIVITIES:
Proceeds from the issuance of long-term debt	994,705	1,610,449
Payment of debt issuance costs - revolving credit facility	0	(3,770)
Payments related to conversion of senior notes	0	(147,629)
Repurchase of common stock	(525,144)	(986,581)
Proceeds from exercise of stock options	9,766	12,825
Excess tax benefits on stock-based awards and other equity deductions	61,470	68,241
Net cash provided by financing activities	540,797	553,535
Effect of exchange rate changes on cash and cash equivalents	4,616	(144,680)
Net increase (decrease) in cash and cash equivalents	1,216,453	(1,259,702)
Cash and cash equivalents, beginning of period	1,477,265	3,148,651
Cash and cash equivalents, end of period	2,693,718	1,888,949
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid during the period for income taxes	496,403	472,350
Cash paid during the period for interest	43,727	13,537
Non-cash investing activity for contingent consideration	$ 0	$ 9,170