Intangible Assets - Schedules (Details) - Licenses - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Licenses
Balance at beginning of year	$ 2,186	$ 2,223
Acquisitions	267	8
Transferred to Assets held for sale	0	(51)
Divestitures	(10)	(11)
Exchanges - Licenses received	26	18
Exchanges - Licenses surrendered	0	(1)
Capitalized interest	2	0
Balance at end of year	$ 2,471	$ 2,186

The increase (decrease) during the period in book value of long-lived assets that the reporting entity plans to sell within one year (or one business cycle).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

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

+ References

No definition available.

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- Definition

Amount of divestiture of an asset lacking physical substance and having a projected indefinite period of benefit to fair value. Excludes financial assets and goodwill.

+ References

No definition available.

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- Definition

Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, from an acquisition.

+ References

No definition available.

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- Definition

Amount of interest capitalized during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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- Definition

Amount of assets received, excluding financial assets and goodwill, lacking physical substance with an indefinite life, from an exchange.

+ References

No definition available.

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- Definition

Amount of assets disposed of, excluding financial assets and goodwill, lacking physical substance with an indefinite life, in an exchange.

+ References

No definition available.

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