| EBP, Schedule of Asset Held for Investment [Table Text Block] |
| | | | | | | | | | | | | | | BELLSOUTH SAVINGS AND SECURITY PLAN | EIN 58-1533433, PLAN NO. 004 | SCHEDULE H, LINE 4(i) - SCHEDULE OF ASSETS (HELD AT END OF YEAR) | December 31, 2025 | | (Dollars in Thousands) | | | | | | | Identity of Issue | Interest Rate | Maturity Date | Number of Shares/Units | Current Value | | Common Stocks | | | | | | * AT&T INC | | | 7,958,265 | $ | 197,683 | | | | | | | | Mutual Funds or Exchange-Traded Funds | | | | | | * DREYFUS GOVT CAS MGMT INST 289 | | 12/31/2075 | 2,475,436 | 2,476 | | | | | | | | U.S. Index Stock Funds | | | | | | * BARCLAYS GLOBAL INVS N A INVT | | | 2,520,362 | 368,449 | | * BLACKROCK RUSSELL 1000 INDEX FUND | | | 5,078,174 | 479,575 | | * EXTENDED EQUITY MARKET FUND F | | | 692,299 | 93,984 | | | * BGI US EQUITY MARKET FUND F | | | 236,569 | 61,440 | | | Total U.S. Index Stock Funds | | | | 1,003,448 | | | | | | | | International Index Stock Fund | | | | | | * BGI MSCI ACWI EX-US INDEX | | | 2,332,426 | 108,881 | | | | | | | | Asset Allocation Funds | | | | | | * LIFEPATH 2065 FUND | | | 87,682 | 1,829 | | | * LIFEPATH 2060 FUND | | | 22,696 | 661 | | | * LIFEPATH INDEX 2055 FUND | | | 29,571 | 1,476 | | | * LIFEPATH INDEX 2050 FUND | | | 336,041 | 12,709 | | | * LIFEPATH INDEX 2045 FUND | | | 2,005,120 | 88,368 | | | * LIFEPATH INDEX 2040 FUND | | | 4,873,970 | 216,790 | | | * LIFEPATH INDEX 2035 FUND | | | 5,373,411 | 203,120 | | | * LIFEPATH INDEX 2030 FUND | | | 3,442,812 | 126,580 | | | * LIFEPATH INDEX RETIREMENT FUND | | | 5,574,267 | 167,184 | | | Total Asset Allocation Funds | | | | 818,717 | | | | | | | | | | | | | | | | | | * Notes Receivable from Participants | 4.25% - 10.50% | | | 45,737 | | | | | | | | Total | | | | $ | 2,176,942 | | | | | | | | * Party-in-Interest | | | | | | | | | |
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