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Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	Feb. 25, 2020	Dec. 31, 2019	Dec. 31, 2018
Loss Contingency, Estimate [Abstract]
Accrual for legal proceedings and unasserted claims		$ 0	$ 0
FCC license auction, percent of bid credit in each auction			25.00%
Subsequent Event
Long-term Purchase Commitment [Line Items]
Commitment to purchase assets	$ 146

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349

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Minimum amount of purchase arrangement maturing in the next fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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FCC License Auction, Percent of Bid Credit in Each Auction

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