v3.21.1

Document and Entity Information | May 17, 2021
--- | ---
Document And Entity Information [Line Items] |
Amendment Flag | false
Entity Central Index Key | 0000732717
Document Type | 8-K
Document Period End Date | May 17, 2021
Entity Registrant Name | AT&T INC.
Entity Incorporation State Country Code | DE
Entity File Number | 001-08610
Entity Tax Identification Number | 43-1301883
Entity Address, Address Line One | 208 S. Akard St.
Entity Address, City or Town | Dallas
Entity Address, State or Province | TX
Entity Address, Postal Zip Code | 75202
City Area Code | (210)
Local Phone Number | 821-4105
Written Communications | true
Soliciting Material | false
Pre Commencement Tender Offer | false
Pre Commencement Issuer Tender Offer | false
Entity Emerging Growth Company | false
Common Stock [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | Common Shares (Par Value $1.00 Per Share)
Trading Symbol | T
Security Exchange Name | NYSE
Series A Preferred Stock [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | Depositary Shares, each representing a 1/1000th interest in a share of 5.000% Perpetual Preferred Stock, Series A
Trading Symbol | T PRA
Security Exchange Name | NYSE
Series C Preferred Stock [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | Depositary Shares, each representing a 1/1000th interest in a share of 4.750% Perpetual Preferred Stock, Series C
Trading Symbol | T PRC
Security Exchange Name | NYSE
ATT Inc 2650 Global Notes Due December 172021 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 2.650% Global Notes due December 17, 2021
Trading Symbol | T 21B
Security Exchange Name | NYSE
ATT Inc 1450 Global Notes Due June 12022 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 1.450% Global Notes due June 1, 2022
Trading Symbol | T 22B
Security Exchange Name | NYSE
ATT Inc 2500 Global Notes Due March 152023 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 2.500% Global Notes due March 15, 2023
Trading Symbol | T 23
Security Exchange Name | NYSE
ATT Inc 2750 Global Notes Due May 192023 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 2.750% Global Notes due May 19, 2023
Trading Symbol | T 23C
Security Exchange Name | NYSE
ATT Inc Floating Rate Due September 52023 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. Floating Rate Global Notes due September 5, 2023
Trading Symbol | T 23D
Security Exchange Name | NYSE
ATT Inc 1050 Global Notes Due September 52023 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 1.050% Global Notes due September 5, 2023
Trading Symbol | T 23E
Security Exchange Name | NYSE
ATT Inc 1300 Global Notes Due September 52023 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 1.300% Global Notes due September 5, 2023
Trading Symbol | T 23A
Security Exchange Name | NYSE
ATT Inc 1950 Global Notes Due September 152023 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 1.950% Global Notes due September 15, 2023
Trading Symbol | T 23F
Security Exchange Name | NYSE
ATT Inc 2400 Global Notes Due March 152024 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 2.400% Global Notes due March 15, 2024
Trading Symbol | T 24A
Security Exchange Name | NYSE
ATT Inc 3500 Global Notes Due December 172025 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 3.500% Global Notes due December 17, 2025
Trading Symbol | T 25
Security Exchange Name | NYSE
ATT Inc 0250 Global Notes Due March 42026 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 0.250% Global Notes due March 4, 2026
Trading Symbol | T 26E
Security Exchange Name | NYSE
Att Inc .1.800 Global Notes Due September 520262 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 1.800% Global Notes due September 5, 2026
Trading Symbol | T 26D
Security Exchange Name | NYSE
ATT Inc 2900 Percent Global Notes Due December 42026 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 2.900% Global Notes due December 4, 2026
Trading Symbol | T 26A
Security Exchange Name | NYSE
ATT Inc 2350 Global Notes Due September 52029 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 2.350% Global Notes due September 5, 2029
Trading Symbol | T 29D
Security Exchange Name | NYSE
ATT Inc 4375 Global Notes Due September 142029 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 4.375% Global Notes due September 14, 2029
Trading Symbol | T 29B
Security Exchange Name | NYSE
ATT Inc 2600 Global Notes Due December 172029 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 2.600% Global Notes due December 17, 2029
Trading Symbol | T 29A
Security Exchange Name | NYSE
ATT Inc 0800 Global Notes Due March 42030 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 0.800% Global Notes due March 4, 2030
Trading Symbol | T 30B
Security Exchange Name | NYSE
ATT Inc 3550 Global Notes Due December 172032 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 3.550% Global Notes due December 17, 2032
Trading Symbol | T 32
Security Exchange Name | NYSE
ATT Inc 5200 Global Notes Due November 182033 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 5.200% Global Notes due November 18, 2033
Trading Symbol | T 33
Security Exchange Name | NYSE
ATT Inc 3375 Global Notes Due March 152034 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 3.375% Global Notes due March 15, 2034
Trading Symbol | T 34
Security Exchange Name | NYSE
ATT Inc 2450 Global Notes Due March 152035 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 2.450% Global Notes due March 15, 2035
Trading Symbol | T 35
Security Exchange Name | NYSE
ATT Inc 3150 Global Notes Due September 42036 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 3.150% Global Notes due September 4, 2036
Trading Symbol | T 36A
Security Exchange Name | NYSE
Att Inc .1.800 Global Notes Due September 1420391 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 1.800% Global Notes due September 14, 2039
Trading Symbol | T 39B
Security Exchange Name | NYSE
ATT Inc 7000 Global Notes Due April 302040 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 7.000% Global Notes due April 30, 2040
Trading Symbol | T 40
Security Exchange Name | NYSE
ATT Inc 4250 Global Notes Due June 12043 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 4.250% Global Notes due June 1, 2043
Trading Symbol | T 43
Security Exchange Name | NYSE
ATT Inc 4875 Global Notes Due June 12044 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 4.875% Global Notes due June 1, 2044
Trading Symbol | T 44
Security Exchange Name | NYSE
Att Inc 4000 Global Notes Due June 12049 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 4.000% Global Notes due June 1, 2049
Trading Symbol | T 49A
Security Exchange Name | NYSE
Att Inc 4250 Global Notes Due March 12050 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 4.250% Global Notes due March 1, 2050
Trading Symbol | T 50
Security Exchange Name | NYSE
ATT Inc 5350 Global Notes Due November 12066 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 5.350% Global Notes due November 1, 2066
Trading Symbol | TBB
Security Exchange Name | NYSE
ATT Inc 5625 Global Notes Due August 12067 [Member] |
Document And Entity Information [Line Items] |
Security 12b Title | AT&T Inc. 5.625% Global Notes due August 1, 2067
Trading Symbol | TBC
Security Exchange Name | NYSE

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