Debt and Other Obligations (Scheduled Contractual Maturities) (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Contractual Maturities - 2020	$ 253
Contractual Maturities - 2021	1,675
Contractual Maturities - 2022	1,000
Contractual Maturities - 2023	3,604
Contractual Maturities - 2024	3,172
Contractual Maturities - Thereafter	8,531
Total Cash Obligations	18,235
Unamortized Discounts	(114)
Total Debt and Other Obligations Outstanding	$ 18,121
Tower Revenue Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Increase (Decrease)	5.00%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Incremental percentage increase (decrease) in the stated rate on a debt instrument.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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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 of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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