Intangible Assets - Narrative (Details)	12 Months Ended
Dec. 31, 2019 USD ($) license	Dec. 31, 2017 USD ($)
Indefinite-lived Intangible Assets [Line Items]
Total winning bid	$ 256,000,000
Goodwill
Loss on impairment		$ 370,000,000
Goodwill		$ 0
Auction 101
Indefinite-lived Intangible Assets [Line Items]
Licenses won \| license	408
Auction 102
Indefinite-lived Intangible Assets [Line Items]
Licenses won \| license	282

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Total number of licenses won in an FCC license auction.

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The total winning bid amount in a FCC license auction.

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