Weighted average interest rate of long-term debt outstanding calculated at point in time.

No definition available.

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

+ Details

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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- Definition

Describes the event or transaction that occurred between the balance sheet date and the date the financial statements are issued or available to be issued.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Definition

Date the event occurred after the balance sheet date but before financial statements are issues or available to be issued, in CCYY-MM-DD format.

+ References

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Additional Financial Information - Subsequent Event (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended		6 Months Ended
	Aug. 31, 2020	Jul. 31, 2020	Jun. 30, 2020	Jun. 30, 2019
Subsequent Event [Line Items]
Repayment of long-term debt			$ 17,284	$ 16,124
Global Notes Due 2022 [Member]
Subsequent Event [Line Items]
Subsequent Event, Description		In July 2020, we completed redemptions of $4,264 of AT&T, WarnerMedia and DIRECTV notes due 2022, with an average interest rate of 3.4%.
Repayment of long-term debt		$ 4,264
Weighted Average Interest Rate		3.40%
AT&T Global Notes Due 2028 To 2061 [Member]
Subsequent Event [Line Items]
Subsequent Event, Description	In August 2020, we issued $11,000 of global notes due 2028 to 2061, with an average interest rate of 2.7%.
Proceeds from Issuance of Debt	$ 11,000
Weighted Average Interest Rate	2.70%
Subsequent Event [Member] \| Global Notes Due 2022 [Member]
Subsequent Event [Line Items]
Subsequent Event, Date		Jul. 31, 2020
Subsequent Event [Member] \| AT&T Global Notes Due 2028 To 2061 [Member]
Subsequent Event [Line Items]
Subsequent Event, Date	Aug. 31, 2020