Indefinite lived Intangible Assets, Exchanges, Received

No definition available.

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- Definition

Indefinite lived Intangible Assets, Exchanges, Surrendered

+ References

No definition available.

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- Definition

Initial Deposits

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of consideration transferred in asset acquisition. Includes, but is not limited to, cash, liability incurred by acquirer, and equity interest issued by acquirer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 50
-Section 30
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123362884&loc=d3e9215-128498

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 50
-Section 55
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6829253&loc=SL6831962-166255

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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- Definition

Amount of gain (loss) on sale or disposal of intangible assets.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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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.

+ Details

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Intangible Assets (Narrative) (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
Intangible Assets (Narrative) (Details) - USD ($)	Feb. 28, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Mar. 31, 2021
Acquired Indefinite-lived Intangible Assets [Line Items]
Initial Deposits		$ 5,400,000		$ 5,400,000		$ 2,300,000
Impairment charges		0	$ 0	0	$ 0
Gain (Loss) on Disposition of Intangible Assets		10,230,000	$ 829,000	10,230,000	$ (3,849,000)
Wireless Licenses [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Asset Acquisition, Consideration Transferred				8,800,000
Exchanges - broadband licenses received				13,600,000
Exchanges - narrowband licenses surrendered				3,400,000
Gain (Loss) on Disposition of Intangible Assets				10,200,000
Prepaid Expenses and Other Current Assets [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Initial Deposits		4,800,000		4,800,000		1,900,000
Other Assets [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Initial Deposits		$ 600,000		600,000		$ 500,000
Wireless Licenses [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Acquisitions				8,769,000
Exchanges - broadband licenses received				13,611,000
Exchanges - narrowband licenses surrendered				3,381,000
SDG&E [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Asset Acquisition, Consideration Transferred	$ 50,000,000.0
Third Parties [Member] \| Wireless Licenses [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Asset Acquisition, Consideration Transferred				6,800,000
Anti-Windfall [Member] \| Wireless Licenses [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Asset Acquisition, Consideration Transferred				$ 2,000,000.0