Defined Benefit Plan Number Of Participants

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 808
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479402/808-10-50-1

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

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-Topic 715
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-Section 55
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+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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- Definition

Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Pension and Postretirement Benefits (AT&T Pension Benefits Plan) (Details) - Pension Plan		3 Months Ended			9 Months Ended
	Apr. 26, 2023 USD ($) numberOfParticipants	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement			$ 8,050,000,000
Defined Benefit Plan Number Of Participants \| numberOfParticipants	96,000
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 0
Settlement (gain) loss		$ 0		$ 0	$ 363,000,000	$ 0