CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Assets [Abstract]
Property, plant and equipment, accumulated depreciation	$ 7,002,823	$ 6,431,843
Amortizable intangible assets, accumulated amortization	4,891,643	4,409,312
Accounts receivable, trade allowance for doubtful accounts	$ 24,369	$ 25,198
Stockholders' Deficiency:
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	100,000,000	100,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Treasury Stock, Shares, Acquired	21,748	6,629,415
Common stock, shares outstanding (in shares)	454,653,279
Restricted Investments, Noncurrent	$ 2,402,486	$ 2,250,854
Cash and cash equivalents	232,452	278,422
Restricted cash	264	264
Derivative contracts	3,555	50,785
Amounts due from affiliates	3,892	4,262
Prepaid Expense and Other Assets, Current	170,555	200,252
Accounts receivable, trade (less allowance for doubtful accounts of $13,420 and $11,677)	434,011	442,581
Treasury Stock, Value	0	(163,866)
Accumulated other comprehensive income	$ 9,421	$ 3,646
Common Class A
Stockholders' Deficiency:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	4,000,000,000	4,000,000,000
Common stock, shares issued (in shares)	268,886,795	297,203,087
Common stock, shares outstanding (in shares)	268,865,047	290,573,672
Common Class B
Stockholders' Deficiency:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares outstanding (in shares)	185,788,232	185,895,903
Common Class C
Stockholders' Deficiency:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	4,000,000,000	4,000,000,000
Common stock, shares issued (in shares)	0	0
Common stock, shares outstanding (in shares)	0	0