Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net income	$ 255,337	$ 167,767
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	767,182	622,135
Stock-based compensation	139,849	129,602
Amortization of intangible assets	153,443	128,068
Amortization of debt issuance costs and debt discounts and premiums	10,609	20,100
Provision for allowance for doubtful accounts	4,886	6,889
Gain on asset sales	(6,013)	0
Loss on debt extinguishment	39,214	42,103
Other items	13,040	3,437
Changes in operating assets and liabilities:
Accounts receivable	(85,126)	(202,430)
Income taxes, net	(32,876)	(53,608)
Other assets	(22,409)	29,046
Accounts payable and accrued expenses	4,782	44,952
Other liabilities	14,879	6,293
Net cash provided by operating activities	1,256,797	944,354
Cash flows from investing activities:
Purchases of investments	(55,181)	(57,926)
Sales of investments	74,376	32,867
Business acquisitions, net of cash and restricted cash acquired	(829,185)	(3,628,526)
Purchases of real estate	(136,612)	(64,964)
Purchases of other property, plant and equipment	(1,415,509)	(946,048)
Proceeds from sale of assets, net of cash transferred	12,154	47,767
Net cash used in investing activities	(2,349,957)	(4,616,830)
Cash flows from financing activities:
Proceeds from employee equity awards	50,103	41,625
Payment of dividends and special distribution	(554,742)	(463,914)
Proceeds from public offering of common stock, net of issuance costs	273,873	2,126,341
Proceeds from senior notes	929,850	2,449,700
Proceeds from loans payable	424,650	1,059,800
Repayments of capital lease and other financing obligations	(89,655)	(60,252)
Repayments of mortgage and loans payable	(429,498)	(63,520)
Repayment of senior notes	0	(500,000)
Debt extinguishment costs	(20,556)	(23,020)
Debt issuance costs	(12,218)	(56,886)
Other financing activities	0	(900)
Net cash provided by financing activities	571,807	4,508,974
Effect of foreign currency exchange rates on cash, cash equivalents and restricted cash	(30,944)	26,450
Net increase (decrease) in cash, cash equivalents and restricted cash	(552,297)	862,948
Cash, cash equivalents and restricted cash at beginning of period	1,450,701	773,247
Cash, cash equivalents and restricted cash at end of period	898,404	1,636,195
Cash and cash equivalents	870,486	1,599,988
Current portion of restricted cash included in other current assets	17,287	25,079
Non-current portion of restricted cash included in other assets	$ 10,631	$ 11,128