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Estimated network reinvestment from First Responders Network Authority. This estimate was calculated by the reporting entity.

No definition available.

Name:	t_EstimatedNetworkReinvestment
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The First Responder Network Authoritys generally recurring costs associated with normal operation expenses.

No definition available.

Name:	t_FirstResponderNetworkAuthorityOperatingExpenses
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The First Responder Network Authoritys generally recurring costs associated with normal operations expenses adjusted for inflation over the life of the contract. This estimate was calculated by the reporting entity.

No definition available.

Name:	t_FirstResponderNetworkAuthorityOperatingExpensesAdjustedForInflation
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- References

No definition available.

Name:	t_GovernmentContractsSubjectToRenegotiationLineItems
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The number of states and/or jurisdictions the entity operates.

No definition available.

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The total sustainability payment paid based on the number of states that have opted-in to the program.

No definition available.

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The total sustainability payment commitment paid based on the number of states that have opted-in to the program.

No definition available.

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Amount of contractual obligation due 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.

No definition available.

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Amount of contractual obligation due in 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.

No definition available.

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Amount of contractual obligation due in the fourth 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.

No definition available.

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Amount of contractual obligation due in the next 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.

No definition available.

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Amount of contractual obligation due in the second 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.

No definition available.

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Amount of contractual obligation due in the third 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.

No definition available.

Name:	us-gaap_ContractualObligationDueInThirdYear
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- References

No definition available.

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Amount of renegotiation refunds which have been determined to be probable and reasonably estimated at the balance sheet date.

No definition available.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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Data Type:	xbrli:monetaryItemType
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Data Type:	na
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Name:	srt_StatementGeographicalAxis=country_US
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