Line Of Credit Facility Covenant Debt Ratio

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.

+ References

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the credit facility first became available, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

Name:	us-gaap_ExternalCreditRatingByGroupingAxis=t_LowCreditRatingMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=t_LoanAMember
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- Details

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Debt (Syndicated Credit Agreement) (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended
	Jun. 30, 2016	Jan. 31, 2015	Dec. 31, 2016	Mar. 31, 2015
Syndicated Credit Agreement [Member]
Debt Instrument [Line Items]
Face amount or capacity of debt (in millions)		$ 9,155
Credit agreement - initiation date		Jan. 31, 2015
Credit agreement - advances outstanding				$ 9,155
Ratio of net debt to EBITDA covenant		3.5 to 1
Credit agreement - base rate		Advances bear interest at a rate equal to: (i) the LIBOR for deposits in dollars (adjusted upwards to reflect any bank reserve costs) for a period of three or six months, as applicable, plus (ii) the applicable margin, as set forth in this agreement.
Syndicated Credit Agreement [Member] \| High Credit Rating [Member] \| Additional Margin Upon Default [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		2.00%
Syndicated Credit Agreement [Member] \| Moderate Credit Rating [Member] \| Additional Margin Upon Default [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		2.00%
Syndicated Credit Agreement [Member] \| Low Credit Rating [Member] \| Additional Margin Upon Default [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		2.00%
Loan A [Member]
Debt Instrument [Line Items]
Face amount or capacity of debt (in millions)		$ 6,286
Credit agreement - maturity date		Mar. 02, 2018
Repayments of Debt	$ 4,000
Credit agreement - advances outstanding			$ 2,286
Ratio of net debt to EBITDA covenant		3.5 to 1
Credit agreement - base rate		Advances bear interest at a rate equal to: (i) the LIBOR for deposits in dollars (adjusted upwards to reflect any bank reserve costs) for a period of three or six months, as applicable, plus (ii) the applicable margin, as set forth in this agreement.
Loan A [Member] \| High Credit Rating [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		1.00%
Loan A [Member] \| High Credit Rating [Member] \| Additional Margin Upon Default [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		2.00%
Loan A [Member] \| Moderate Credit Rating [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		1.125%
Loan A [Member] \| Moderate Credit Rating [Member] \| Additional Margin Upon Default [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		2.00%
Loan A [Member] \| Low Credit Rating [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		1.25%
Loan A [Member] \| Low Credit Rating [Member] \| Additional Margin Upon Default [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		2.00%
Loan B [Member]
Debt Instrument [Line Items]
Face amount or capacity of debt (in millions)		$ 2,869
Credit agreement - term description		Amounts borrowed under the Loan B will be subject to amortization from March 2, 2018, with 25 percent of the aggregate principal amount thereof being payable prior to March 2, 2020, and all remaining principal amount due on March 2, 2020.
Repayments of Debt	$ 1,000
Credit agreement - advances outstanding			$ 1,869
Ratio of net debt to EBITDA covenant		3.5 to 1
Credit agreement - base rate		Advances bear interest at a rate equal to: (i) the LIBOR for deposits in dollars (adjusted upwards to reflect any bank reserve costs) for a period of three or six months, as applicable, plus (ii) the applicable margin, as set forth in this agreement.
Loan B [Member] \| High Credit Rating [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		1.125%
Loan B [Member] \| High Credit Rating [Member] \| Additional Margin Upon Default [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		2.00%
Loan B [Member] \| Moderate Credit Rating [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		1.25%
Loan B [Member] \| Moderate Credit Rating [Member] \| Additional Margin Upon Default [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		2.00%
Loan B [Member] \| Low Credit Rating [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		1.375%
Loan B [Member] \| Low Credit Rating [Member] \| Additional Margin Upon Default [Member]
Debt Instrument [Line Items]
Credit agreement - basis spread of variable rate		2.00%