CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net income	$ 994,677	$ 1,021,294	$ 333,040
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Depreciation and amortization	630,435	615,152	591,035
Impairment charges	0	124,892	61,981
Valuation adjustment on disposal group	0	0	316,840
Debt prepayment, refinancing and redemption charges	86,957	33,402	0
Stock-based compensation expense	91,458	67,850	73,061
Deferred income taxes	240,848	41,723	273,660
Equity investment income, net	13,830	8,582	26,449
Loss (gain) on sales of business interests, net	24,248	23,022
Loss (gain) on sales of business interests, net			(85,699)
Other non-cash charges, net	747	49,579	82,374
Changes in operating assets and liabilities, net of effect of acquisitions and divestitures:
Accounts receivable	(21,087)	(79,957)	(81,176)
Inventories	(12,349)	10,158	73,505
Other receivables and other current assets	(79,277)	2,790	236,995
Other long-term assets	(6,123)	6,965	3,497
Accounts payable	37,200	(84,539)	(35,959)
Accrued compensation and benefits	(20,931)	(14,697)	84,165
Other current liabilities	105,637	181,940	(157,462)
Income taxes	(87,391)	95,645	(23,635)
Other long-term liabilities	(19,851)	(31,446)	(1,031)
Net Cash Provided by (Used in) Operating Activities, Total	1,979,028	2,072,355	1,771,640
Cash flows from investing activities:
Additions of property and equipment	(674,541)	(766,546)	(987,138)
Acquisitions	(182,013)	(100,861)	(183,156)
Proceeds from asset and business sales	50,139	3,877,392	150,205
Purchase of debt investments held-to-maturity	(150,701)	(101,462)	(5,963)
Purchase of other debt and equity investments	(3,757)	(5,458)	(8,448)
Proceeds from debt investments held-to-maturity	151,213	95,376	34,862
Proceeds from sale of other debt and equity investments	3,491	3,676	9,526
Purchase of equity method investments	(22,341)	(9,366)	(19,177)
Distributions from equity method investments	3,139	2,589	3,646
Net Cash Provided by (Used in) Investing Activities, Total	(825,371)	2,995,340	(1,005,643)
Cash flows from financing activities:
Borrowings	4,046,775	38,525,850	59,934,750
Payments on long-term debt	(4,110,304)	(40,520,722)	(59,234,946)
Debt Financing And Debt Redemption Costs	(105,848)	(85,319)	(5,027)
Purchase of treasury stock	(1,458,442)	(2,383,816)	(1,161,511)
Distributions to noncontrolling interests	(253,118)	(233,123)	(196,441)
Net (payments) receipts related to stock purchases and awards	(975)
Net (payments) receipts related to stock purchases and awards		11,382	13,577
Contributions from noncontrolling interests	42,966	57,317	52,311
Proceeds from sales of additional noncontrolling interests	0	0	15
Purchases of noncontrolling interests	(7,831)	(68,019)	(28,082)
Net cash used in financing activities	(1,846,777)	(4,696,450)	(625,354)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(13,808)	(1,760)	(3,350)
Less: Net increase (decrease) in cash, cash equivalents and restricted cash	(706,928)	369,485	137,293
Cash, cash equivalents and restricted cash of continuing operations at beginning of the year	1,208,718	415,420	518,920
Cash, cash equivalents and restricted cash of continuing operations at end of the year	501,790	1,208,718	415,420
Discontinued Operations
Cash flows from financing activities:
Less: Net increase (decrease) in cash, cash equivalents and restricted cash	0	(423,813)	240,793
Continuing Operations
Cash flows from financing activities:
Less: Net increase (decrease) in cash, cash equivalents and restricted cash	$ (706,928)	$ 793,298	$ (103,500)