| Document and Entity Information | May 18, 2023 |
| Document And Entity Information [Line Items] | |
| Amendment Flag | false |
| Entity Central Index Key | 0000732717 |
| Document Type | 8-K |
| Document Period End Date | May 18, 2023 |
| 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 | false |
| 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 .2.500 Global Notes Due March 1520237 [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 .2.750 Global Notes Due May 19202311 [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 Global Notes 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 .1.050 Global Notes Due September 52023 Member 20 [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 .1.300 Global Notes Due September 5202312 [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 .1.950 Global Notes Due September 15202313 [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 .2.400 Global Notes Due March 1520241 [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 Floating Rate Global Notes Due March 62025 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | AT&T Inc. Floating Rate Global Notes due March 6, 2025 |
| Trading Symbol | T 25A |
| Security Exchange Name | NYSE |
| Att Inc .3.550 Global Notes Due November 182025 Member 24 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | AT&T Inc. 3.550% Global Notes due November 18, 2025 |
| Trading Symbol | T 25B |
| Security Exchange Name | NYSE |
| Att Inc .3.500 Global Notes Due December 172025 Member 28 [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 .0.250 Global Notes Due March 420262 [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 5202614 [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 .2.900 Global Notes Due December 4202625 [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 .1.600 Global Notes Due May 1920288 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | AT&T Inc. 1.600% Global Notes due May 19, 2028 |
| Trading Symbol | T 28C |
| Security Exchange Name | NYSE |
| Att Inc .2.350 Global Notes Due September 5202915 [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 .4.375 Global Notes Due September 14202916 [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 .2.600 Global Notes Due December 17202926 [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 .0.800 Global Notes Due March 420303 [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 .3.950 Global Notes Due April 302031 Member 30 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | AT&T Inc. 3.950% Global Notes due April 30, 2031 |
| Trading Symbol | T 31F |
| Security Exchange Name | NYSE |
| Att Inc .2.050 Global Notes Due May 1920329 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | AT&T Inc. 2.050% Global Notes due May 19, 2032 |
| Trading Symbol | T 32A |
| Security Exchange Name | NYSE |
| Att Inc .3.550 Global Notes Due December 17203227 [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 .5.200 Global Notes Due November 18203321 [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 .3.375 Global Notes Due March 1520344 [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 .4.300 Global Notes Due November 18203422 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | AT&T Inc. 4.300% Global Notes due November 18, 2034 |
| Trading Symbol | T 34C |
| Security Exchange Name | NYSE |
| Att Inc .2.450 Global Notes Due March 1520355 [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 .3.150 Global Notes Due September 4203617 [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 .2.600 Global Notes Due May 19203810 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | AT&T Inc. 2.600% Global Notes due May 19, 2038 |
| Trading Symbol | T 38C |
| Security Exchange Name | NYSE |
| Att Inc .1.800 Global Notes Due September 14203918 [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 .7.000 Global Notes Due April 30204029 [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 .4.250 Global Notes Due June 12043 Member 33 [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 .4.875 Global Notes Due June 1204431 [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 .4.000 Global Notes Due June 1204932 [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 .4.250 Global Notes Due March 120506 [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 .3.750 Global Notes Due September 1205019 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | AT&T Inc. 3.750% Global Notes due September 1, 2050 |
| Trading Symbol | T 50A |
| Security Exchange Name | NYSE |
| Att Inc .5.350 Global Notes Due November 1206623 [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 |
