Debt (Schedule of Principal Values, Fair Values, and Carrying Values of Debt) (Details) - USD ($)	6 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal Balance	$ 10,662,000,000	$ 10,414,000,000
Fair Value	10,835,541,000	10,543,695,000
Carrying Value	10,579,568,000	10,334,425,000
Less: current maturities of long-term debt	(24,000,000)	(522,090,000)
Total long-term debt, net of current maturities	$ 10,555,568,000	9,812,335,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Apr. 11, 2023
Principal Balance		490,000,000
Fair Value		490,000,000
Carrying Value		490,000,000
2018 Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Apr. 11, 2025
Principal Balance	$ 2,352,000,000	2,364,000,000
Fair Value	2,269,680,000	2,369,910,000
Carrying Value	$ 2,335,750,000	2,346,183,000
2013-2C Tower Securities [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Apr. 11, 2023
Principal Balance	$ 575,000,000	575,000,000
Fair Value	606,211,000	585,954,000
Carrying Value	$ 571,459,000	570,866,000
2014-2C Tower Securities [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Oct. 08, 2024
Principal Balance	$ 620,000,000	620,000,000
Fair Value	678,522,000	644,912,000
Carrying Value	$ 615,663,000	615,205,000
2015-1C Tower Securities [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Oct. 08, 2020
Principal Balance	$ 500,000,000	500,000,000
Fair Value	502,605,000	502,095,000
Carrying Value	$ 499,298,000	498,090,000
2016-1C Tower Securities [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Jul. 09, 2021
Principal Balance	$ 700,000,000	700,000,000
Fair Value	712,838,000	704,095,000
Carrying Value	$ 697,930,000	696,936,000
2017-1C Tower Securities [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Apr. 11, 2022
Principal Balance	$ 760,000,000	760,000,000
Fair Value	781,113,000	763,405,000
Carrying Value	$ 756,104,000	755,061,000
2018-1C Tower Securities [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Mar. 09, 2023
Principal Balance	$ 640,000,000	640,000,000
Fair Value	679,430,000	658,266,000
Carrying Value	$ 635,187,000	634,344,000
2019-1C Tower Securities [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Jan. 12, 2025
Principal Balance	$ 1,165,000,000	1,165,000,000
Fair Value	1,229,017,000	1,158,057,000
Carrying Value	$ 1,154,002,000	1,153,086,000
2014 Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Jul. 15, 2022
Principal Balance		750,000,000
Fair Value		760,313,000
Carrying Value		743,580,000
2016 Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Sep. 01, 2024
Principal Balance	$ 1,100,000,000	1,100,000,000
Fair Value	1,126,125,000	1,142,625,000
Carrying Value	$ 1,087,566,000	1,086,241,000
2017 Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Oct. 01, 2022
Principal Balance	$ 750,000,000	750,000,000
Fair Value	753,750,000	764,063,000
Carrying Value	$ 745,728,000	$ 744,833,000
2020 Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Feb. 15, 2027
Principal Balance	$ 1,500,000,000
Fair Value	1,496,250,000
Carrying Value	$ 1,480,881,000

Face (par) amount of debt instrument at time of issuance.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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