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v3.25.3

Fair Value (Tables) | 9 Months Ended
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Sep. 30, 2025
Fair Value Disclosures [Abstract] |
Schedule of Assets and Liabilities Measured and Recorded at Fair Value on a Recurring Basis | The following table presents assets and liabilities for DTE Energy measured and recorded at fair value on a recurring basis:
| September 30, 2025 |  | December 31, 2024
| Level 1 |  | Level 2 |  | Level 3 |  | Other(a) |  | Netting(b) |  | Net Balance |  | Level 1 |  | Level 2 |  | Level 3 |  | Other(a) |  | Netting(b) |  | Net Balance
| (In millions)
Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash equivalents and Restricted cash(c) | $ | 24 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 24 |  |  | $ | 11 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 11 |
Nuclear decommissioning trusts |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity securities | 958 |  |  | — |  |  | — |  |  | 181 |  |  | — |  |  | 1,139 |  |  | 856 |  |  | — |  |  | — |  |  | 147 |  |  | — |  |  | 1,003 |
Fixed income securities | 129 |  |  | 452 |  |  | — |  |  | 126 |  |  | — |  |  | 707 |  |  | 124 |  |  | 414 |  |  | — |  |  | 112 |  |  | — |  |  | 650 |
Private equity and other | 8 |  |  | — |  |  | — |  |  | 354 |  |  | — |  |  | 362 |  |  | 16 |  |  | — |  |  | — |  |  | 333 |  |  | — |  |  | 349 |
Hedge funds and similar investments | 225 |  |  | 16 |  |  | — |  |  | — |  |  | — |  |  | 241 |  |  | 151 |  |  | 16 |  |  | — |  |  | 61 |  |  | — |  |  | 228 |
Cash equivalents | 31 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 31 |  |  | 26 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 26 |
Other investments(d) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity securities | 81 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 81 |  |  | 72 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 72 |
Fixed income securities | 8 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 8 |  |  | 7 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 7 |
Cash equivalents | 31 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 31 |  |  | 29 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 29 |
Derivative assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commodity contracts(e) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Natural gas | 215 |  |  | 30 |  |  | 99 |  |  | — |  |  | (255) |  |  | 89 |  |  | 242 |  |  | 81 |  |  | 105 |  |  | — |  |  | (285) |  |  | 143 |
Electricity | 80 |  |  | 76 |  |  | 35 |  |  | — |  |  | (126) |  |  | 65 |  |  | 67 |  |  | 69 |  |  | 51 |  |  | — |  |  | (116) |  |  | 71 |
Environmental & Other | 12 |  |  | 43 |  |  | 19 |  |  | — |  |  | (56) |  |  | 18 |  |  | 1 |  |  | 47 |  |  | 10 |  |  | — |  |  | (46) |  |  | 12 |
Other contracts | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 21 |  |  | — |  |  | — |  |  | — |  |  | 21 |
Total derivative assets | 307 |  |  | 149 |  |  | 153 |  |  | — |  |  | (437) |  |  | 172 |  |  | 310 |  |  | 218 |  |  | 166 |  |  | — |  |  | (447) |  |  | 247 |
Total | $ | 1,802 |  |  | $ | 617 |  |  | $ | 153 |  |  | $ | 661 |  |  | $ | (437) |  |  | $ | 2,796 |  |  | $ | 1,602 |  |  | $ | 648 |  |  | $ | 166 |  |  | $ | 653 |  |  | $ | (447) |  |  | $ | 2,622 |
Liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commodity contracts(e) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Natural gas | $ | (190) |  |  | $ | (30) |  |  | $ | (80) |  |  | $ | — |  |  | $ | 230 |  |  | $ | (70) |  |  | $ | (217) |  |  | $ | (70) |  |  | $ | (123) |  |  | $ | — |  |  | $ | 272 |  |  | $ | (138) |
Electricity | (86) |  |  | (47) |  |  | (30) |  |  | — |  |  | 131 |  |  | (32) |  |  | (71) |  |  | (52) |  |  | (27) |  |  | — |  |  | 114 |  |  | (36) |
Environmental & Other | (12) |  |  | (29) |  |  | — |  |  | — |  |  | 41 |  |  | — |  |  | (2) |  |  | (39) |  |  | (3) |  |  | — |  |  | 44 |  |  | — |
Other contracts | — |  |  | (1) |  |  | — |  |  | — |  |  | — |  |  | (1) |  |  | — |  |  | (1) |  |  | — |  |  | — |  |  | — |  |  | (1) |
Total | $ | (288) |  |  | $ | (107) |  |  | $ | (110) |  |  | $ | — |  |  | $ | 402 |  |  | $ | (103) |  |  | $ | (290) |  |  | $ | (162) |  |  | $ | (153) |  |  | $ | — |  |  | $ | 430 |  |  | $ | (175) |
Net Assets (Liabilities) at end of period | $ | 1,514 |  |  | $ | 510 |  |  | $ | 43 |  |  | $ | 661 |  |  | $ | (35) |  |  | $ | 2,693 |  |  | $ | 1,312 |  |  | $ | 486 |  |  | $ | 13 |  |  | $ | 653 |  |  | $ | (17) |  |  | $ | 2,447 |
Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | $ | 255 |  |  | $ | 97 |  |  | $ | 92 |  |  | $ | — |  |  | $ | (317) |  |  | $ | 127 |  |  | $ | 223 |  |  | $ | 170 |  |  | $ | 106 |  |  | $ | — |  |  | $ | (326) |  |  | $ | 173 |
Noncurrent | 1,547 |  |  | 520 |  |  | 61 |  |  | 661 |  |  | (120) |  |  | 2,669 |  |  | 1,379 |  |  | 478 |  |  | 60 |  |  | 653 |  |  | (121) |  |  | 2,449 |
Total Assets | $ | 1,802 |  |  | $ | 617 |  |  | $ | 153 |  |  | $ | 661 |  |  | $ | (437) |  |  | $ | 2,796 |  |  | $ | 1,602 |  |  | $ | 648 |  |  | $ | 166 |  |  | $ | 653 |  |  | $ | (447) |  |  | $ | 2,622 |
Liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | $ | (219) |  |  | $ | (74) |  |  | $ | (55) |  |  | $ | — |  |  | $ | 300 |  |  | $ | (48) |  |  | $ | (219) |  |  | $ | (129) |  |  | $ | (93) |  |  | $ | — |  |  | $ | 323 |  |  | $ | (118) |
Noncurrent | (69) |  |  | (33) |  |  | (55) |  |  | — |  |  | 102 |  |  | (55) |  |  | (71) |  |  | (33) |  |  | (60) |  |  | — |  |  | 107 |  |  | (57) |
Total Liabilities | $ | (288) |  |  | $ | (107) |  |  | $ | (110) |  |  | $ | — |  |  | $ | 402 |  |  | $ | (103) |  |  | $ | (290) |  |  | $ | (162) |  |  | $ | (153) |  |  | $ | — |  |  | $ | 430 |  |  | $ | (175) |
Net Assets (Liabilities) at end of period | $ | 1,514 |  |  | $ | 510 |  |  | $ | 43 |  |  | $ | 661 |  |  | $ | (35) |  |  | $ | 2,693 |  |  | $ | 1,312 |  |  | $ | 486 |  |  | $ | 13 |  |  | $ | 653 |  |  | $ | (17) |  |  | $ | 2,447 |
_______________________________________ (a)Amounts represent assets valued at NAV as a practical expedient for fair value. (b)Amounts represent the impact of master netting agreements that allow DTE Energy to net gain and loss positions and cash collateral held or placed with the same counterparties. (c)Amounts include $22 million and $8 million recorded in Restricted cash on DTE Energy's Consolidated Statements of Financial Position at September 30, 2025 and December 31, 2024, respectively. All other amounts are included in Cash and cash equivalents on DTE Energy's Consolidated Statements of Financial Position. (d)Excludes cash surrender value of life insurance investments and certain securities classified as held-to-maturity that are recorded at amortized cost and not material to the consolidated financial statements. (e)For contracts with a clearing agent, DTE Energy nets all activity across commodities. This can result in some individual commodities having a contra balance. The following table presents assets for DTE Electric measured and recorded at fair value on a recurring basis as of:
| September 30, 2025 |  | December 31, 2024
| Level 1 |  | Level 2 |  | Level 3 |  | Other(a) |  | Net Balance |  | Level 1 |  | Level 2 |  | Level 3 |  | Other(a) |  | Net Balance
| (In millions)
Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted cash | $ | 22 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 22 |  |  | $ | 8 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 8 |
Nuclear decommissioning trusts |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity securities | 958 |  |  | — |  |  | — |  |  | 181 |  |  | 1,139 |  |  | 856 |  |  | — |  |  | — |  |  | 147 |  |  | 1,003 |
Fixed income securities | 129 |  |  | 452 |  |  | — |  |  | 126 |  |  | 707 |  |  | 124 |  |  | 414 |  |  | — |  |  | 112 |  |  | 650 |
Private equity and other | 8 |  |  | — |  |  | — |  |  | 354 |  |  | 362 |  |  | 16 |  |  | — |  |  | — |  |  | 333 |  |  | 349 |
Hedge funds and similar investments | 225 |  |  | 16 |  |  | — |  |  | — |  |  | 241 |  |  | 151 |  |  | 16 |  |  | — |  |  | 61 |  |  | 228 |
Cash equivalents | 31 |  |  | — |  |  | — |  |  | — |  |  | 31 |  |  | 26 |  |  | — |  |  | — |  |  | — |  |  | 26 |
Other investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity securities | 30 |  |  | — |  |  | — |  |  | — |  |  | 30 |  |  | 26 |  |  | — |  |  | — |  |  | — |  |  | 26 |
Cash equivalents | 19 |  |  | — |  |  | — |  |  | — |  |  | 19 |  |  | 19 |  |  | — |  |  | — |  |  | — |  |  | 19 |
Derivative assets — FTRs | — |  |  | — |  |  | 18 |  |  | — |  |  | 18 |  |  | — |  |  | — |  |  | 9 |  |  | — |  |  | 9 |
Total | $ | 1,422 |  |  | $ | 468 |  |  | $ | 18 |  |  | $ | 661 |  |  | $ | 2,569 |  |  | $ | 1,226 |  |  | $ | 430 |  |  | $ | 9 |  |  | $ | 653 |  |  | $ | 2,318 |
Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | $ | 22 |  |  | $ | — |  |  | $ | 18 |  |  | $ | — |  |  | $ | 40 |  |  | $ | 8 |  |  | $ | — |  |  | $ | 9 |  |  | $ | — |  |  | $ | 17 |
Noncurrent | 1,400 |  |  | 468 |  |  | — |  |  | 661 |  |  | 2,529 |  |  | 1,218 |  |  | 430 |  |  | — |  |  | 653 |  |  | 2,301 |
Total Assets | $ | 1,422 |  |  | $ | 468 |  |  | $ | 18 |  |  | $ | 661 |  |  | $ | 2,569 |  |  | $ | 1,226 |  |  | $ | 430 |  |  | $ | 9 |  |  | $ | 653 |  |  | $ | 2,318 |
_______________________________________ (a)Amounts represent assets valued at NAV as a practical expedient for fair value.
Schedule of Reconciliation of Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis | The following tables present the fair value reconciliation of Level 3 assets and liabilities measured at fair value on a recurring basis for DTE Energy:
| Three Months Ended September 30, 2025 |  | Three Months Ended September 30, 2024
| Natural Gas |  | Electricity |  | Other |  | Total |  | Natural Gas |  | Electricity |  | Other |  | Total
| (In millions)
Net Assets (Liabilities) as of June 30 | $ | (9) |  |  | $ | (8) |  |  | $ | 31 |  |  | $ | 14 |  |  | $ | 3 |  |  | $ | 9 |  |  | $ | 26 |  |  | $ | 38 |
Transfers into Level 3 from Level 2 | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 2 |  |  | — |  |  | 2 |
Transfers from Level 3 into Level 2 | (4) |  |  | — |  |  | — |  |  | (4) |  |  | — |  |  | — |  |  | — |  |  | — |
Total gains (losses) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Included in earnings(a) | 28 |  |  | 130 |  |  | — |  |  | 158 |  |  | 7 |  |  | 105 |  |  | — |  |  | 112 |
Recorded in Regulatory liabilities | — |  |  | — |  |  | (6) |  |  | (6) |  |  | — |  |  | — |  |  | 2 |  |  | 2 |
Purchases, issuances, and settlements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlements | 4 |  |  | (117) |  |  | (6) |  |  | (119) |  |  | (15) |  |  | (87) |  |  | (9) |  |  | (111) |
Net Assets (Liabilities) as of September 30 | $ | 19 |  |  | $ | 5 |  |  | $ | 19 |  |  | $ | 43 |  |  | $ | (5) |  |  | $ | 29 |  |  | $ | 19 |  |  | $ | 43 |
Total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at September 30(a) | $ | 37 |  |  | $ | 19 |  |  | $ | — |  |  | $ | 56 |  |  | $ | (6) |  |  | $ | 75 |  |  | $ | (10) |  |  | $ | 59 |
Total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at September 30 | $ | — |  |  | $ | — |  |  | $ | (5) |  |  | $ | (5) |  |  | $ | — |  |  | $ | — |  |  | $ | 2 |  |  | $ | 2 |
_______________________________________ (a)Amounts are reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, gas, and other — non-utility in DTE Energy's Consolidated Statements of Operations.
| Nine Months Ended September 30, 2025 |  | Nine Months Ended September 30, 2024
| Natural Gas |  | Electricity |  | Other |  | Total |  | Natural Gas |  | Electricity |  | Other |  | Total
| (In millions)
Net Assets (Liabilities) as of December 31 | $ | (18) |  |  | $ | 24 |  |  | $ | 7 |  |  | $ | 13 |  |  | $ | 22 |  |  | $ | 47 |  |  | $ | 6 |  |  | $ | 75 |
Transfers into Level 3 from Level 2 | 2 |  |  | — |  |  | — |  |  | 2 |  |  | 1 |  |  | 1 |  |  | — |  |  | 2 |
Transfers from Level 3 into Level 2 | — |  |  | — |  |  | 2 |  |  | 2 |  |  | — |  |  | — |  |  | — |  |  | — |
Total gains (losses) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Included in earnings(a) | (17) |  |  | 275 |  |  | 2 |  |  | 260 |  |  | 13 |  |  | 196 |  |  | (1) |  |  | 208 |
Recorded in Regulatory liabilities | — |  |  | — |  |  | 20 |  |  | 20 |  |  | — |  |  | — |  |  | 29 |  |  | 29 |
Purchases, issuances, and settlements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlements | 52 |  |  | (294) |  |  | (12) |  |  | (254) |  |  | (41) |  |  | (215) |  |  | (15) |  |  | (271) |
Net Assets (Liabilities) as of September 30 | $ | 19 |  |  | $ | 5 |  |  | $ | 19 |  |  | $ | 43 |  |  | $ | (5) |  |  | $ | 29 |  |  | $ | 19 |  |  | $ | 43 |
Total gains (losses) included in Net Income attributed to the change in unrealized gains (losses) related to assets and liabilities held at September 30(a) | $ | 13 |  |  | $ | 2 |  |  | $ | 1 |  |  | $ | 16 |  |  | $ | (25) |  |  | $ | 156 |  |  | $ | (41) |  |  | $ | 90 |
Total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at September 30 | $ | — |  |  | $ | — |  |  | $ | 18 |  |  | $ | 18 |  |  | $ | — |  |  | $ | — |  |  | $ | 21 |  |  | $ | 21 |
_______________________________________ (a)Amounts are reflected in Operating Revenues — Non-utility operations and Fuel, purchased power, gas, and other — non-utility in DTE Energy's Consolidated Statements of Operations. The following table presents the fair value reconciliation of Level 3 assets and liabilities measured at fair value on a recurring basis for DTE Electric:
| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
| (In millions)
Net Assets as of beginning of period | $ | 30 |  |  | $ | 28 |  |  | $ | 9 |  |  | $ | 7 |
Total gains (losses) recorded in Regulatory liabilities | (6) |  |  | 2 |  |  | 20 |  |  | 29 |
Purchases, issuances, and settlements |  |  |  |  |  |  |
Settlements | (6) |  |  | (9) |  |  | (11) |  |  | (15) |
Net Assets as of September 30 | $ | 18 |  |  | $ | 21 |  |  | $ | 18 |  |  | $ | 21 |
Total gains (losses) included in Regulatory liabilities attributed to the change in unrealized gains (losses) related to assets and liabilities held at September 30 | $ | (5) |  |  | $ | 2 |  |  | $ | 18 |  |  | $ | 21 |
Schedule of Unobservable Inputs Related to Level 3 Assets and Liabilities | The following tables present the unobservable inputs related to DTE Energy's Level 3 assets and liabilities:
|  | September 30, 2025 |  |  |  |  |  |  |  |  |  |  |
Commodity Contracts |  | Derivative Assets |  | Derivative Liabilities |  | Valuation Techniques |  | Unobservable Input |  | Range |  | Weighted Average
|  | (In millions) |  |  |  |  |  |  |  |  |  |  |
Natural Gas |  | $ | 99 |  |  | $ | (80) |  |  | Discounted Cash Flow |  | Forward basis price (per MMBtu) |  | $ | (1.34) |  | — |  | $ | 3.25 | /MMBtu |  | $ | (0.06) | /MMBtu
Electricity |  | $ | 35 |  |  | $ | (30) |  |  | Discounted Cash Flow |  | Forward basis price (per MWh) |  | $ | (19.55) |  | — |  | $ | 18.40 | /MWh |  | $ | (4.36) | /MWh
|  | December 31, 2024 |  |  |  |  |  |  |  |  |  |  |
Commodity Contracts |  | Derivative Assets |  | Derivative Liabilities |  | Valuation Techniques |  | Unobservable Input |  | Range |  | Weighted Average
|  | (In millions) |  |  |  |  |  |  |  |  |  |  |
Natural Gas |  | $ | 105 |  |  | $ | (123) |  |  | Discounted Cash Flow |  | Forward basis price (per MMBtu) |  | $ | (1.24) |  | — |  | $ | 9.96 | /MMBtu |  | $ | (0.05) | /MMBtu
Electricity |  | $ | 51 |  |  | $ | (27) |  |  | Discounted Cash Flow |  | Forward basis price (per MWh) |  | $ | (16.34) |  | — |  | $ | 17.28 | /MWh |  | $ | (2.74) | /MWh
Schedule of Carrying Amount of Fair Value of Financial Instruments | The following table presents the carrying amount and fair value of financial instruments for DTE Energy:
| September 30, 2025 |  | December 31, 2024
| Carrying |  | Fair Value |  | Carrying |  | Fair Value
| Amount |  | Level 1 |  | Level 2 |  | Level 3 |  | Amount |  | Level 1 |  | Level 2 |  | Level 3
| (In millions)
Notes receivable(a), excluding lessor finance leases | $ | 1,268 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,312 |  |  | $ | 884 |  |  | $ | — |  |  | $ | — |  |  | $ | 904 |
Short-term borrowings | $ | 216 |  |  | $ | — |  |  | $ | 216 |  |  | $ | — |  |  | $ | 1,067 |  |  | $ | — |  |  | $ | 1,067 |  |  | $ | — |
Notes payable(b) | $ | 43 |  |  | $ | — |  |  | $ | — |  |  | $ | 43 |  |  | $ | 37 |  |  | $ | — |  |  | $ | — |  |  | $ | 37 |
Long-term debt(c) | $ | 24,802 |  |  | $ | 1,339 |  |  | $ | 20,931 |  |  | $ | 1,381 |  |  | $ | 21,963 |  |  | $ | 725 |  |  | $ | 18,283 |  |  | $ | 1,128 |
_______________________________________ (a)Current portion included in Current Assets — Other on DTE Energy's Consolidated Statements of Financial Position. Carrying value includes credit loss reserves on Notes receivable. (b)Included in Current Liabilities — Other and Other Liabilities — Other on DTE Energy's Consolidated Statements of Financial Position. (c)Includes debt due within one year and excludes finance lease obligations. Carrying value also includes unamortized debt discounts and issuance costs. The following table presents the carrying amount and fair value of financial instruments for DTE Electric:
| September 30, 2025 |  | December 31, 2024
| Carrying |  | Fair Value |  | Carrying |  | Fair Value
| Amount |  | Level 1 |  | Level 2 |  | Level 3 |  | Amount |  | Level 1 |  | Level 2 |  | Level 3
| (In millions)
Notes receivable — Affiliates | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 42 |  |  | $ | — |  |  | $ | — |  |  | $ | 42 |
Notes receivable — Other(a) | $ | 158 |  |  | $ | — |  |  | $ | — |  |  | $ | 164 |  |  | $ | 2 |  |  | $ | — |  |  | $ | — |  |  | $ | 2 |
Short-term borrowings — Affiliates | $ | 1,076 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,076 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Short-term borrowings — Other | $ | 216 |  |  | $ | — |  |  | $ | 216 |  |  | $ | — |  |  | $ | 666 |  |  | $ | — |  |  | $ | 666 |  |  | $ | — |
Notes payable(b) | $ | 24 |  |  | $ | — |  |  | $ | — |  |  | $ | 24 |  |  | $ | 35 |  |  | $ | — |  |  | $ | — |  |  | $ | 35 |
Long-term debt(c) | $ | 12,775 |  |  | $ | — |  |  | $ | 11,724 |  |  | $ | 131 |  |  | $ | 11,881 |  |  | $ | — |  |  | $ | 10,449 |  |  | $ | 127 |
_______________________________________ (a)Included in Other Assets — Other on DTE Electric's Consolidated Statements of Financial Position. (b)Included in Current Liabilities — Other and Other Liabilities — Other on DTE Electric's Consolidated Statements of Financial Position. (c)Includes debt due within one year and excludes finance lease obligations. Carrying value also includes unamortized debt discounts and issuance costs.
Schedule of Fair Value of Nuclear Decommissioning Trust Fund Assets | The following table summarizes DTE Electric's fair value of the nuclear decommissioning trust fund assets:
| September 30, 2025 |  | December 31, 2024
| (In millions)
Fermi 2 | $ | 2,453 |  |  | $ | 2,234 |
Fermi 1 | 3 |  |  | 3 |
Low-level radioactive waste | 24 |  |  | 19 |
| $ | 2,480 |  |  | $ | 2,256 |
Schedule of Realized Gains and Losses and Proceeds from Sale of Securities by Nuclear Decommissioning Trust Funds | The following table sets forth DTE Electric's gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds:
| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
| (In millions)
Realized gains | $ | 27 |  |  | $ | 11 |  |  | $ | 40 |  |  | $ | 41 |
Realized losses | $ | (9) |  |  | $ | (6) |  |  | $ | (26) |  |  | $ | (22) |
Proceeds from sale of securities | $ | 221 |  |  | $ | 91 |  |  | $ | 592 |  |  | $ | 438 |
Schedule of Fair Value and Unrealized Gains and Losses for Nuclear Decommissioning Trust Funds | The following table sets forth DTE Electric's fair value and unrealized gains and losses for the nuclear decommissioning trust funds:
| September 30, 2025 |  | December 31, 2024
| Fair Value |  | Unrealized Gains |  | Unrealized Losses |  | Fair Value |  | Unrealized Gains |  | Unrealized Losses
| (In millions)
Equity securities | $ | 1,139 |  |  | $ | 694 |  |  | $ | (9) |  |  | $ | 1,003 |  |  | $ | 558 |  |  | $ | (16) |
Fixed income securities | 707 |  |  | 18 |  |  | (18) |  |  | 650 |  |  | 16 |  |  | (29) |
Private equity and other | 362 |  |  | 122 |  |  | (9) |  |  | 349 |  |  | 106 |  |  | (8) |
Hedge funds and similar investments | 241 |  |  | 6 |  |  | (5) |  |  | 228 |  |  | 7 |  |  | (5) |
Cash equivalents | 31 |  |  | — |  |  | — |  |  | 26 |  |  | — |  |  | — |
| $ | 2,480 |  |  | $ | 840 |  |  | $ | (41) |  |  | $ | 2,256 |  |  | $ | 687 |  |  | $ | (58) |
Schedule of Fair Value of the Fixed Income Securities Held in Nuclear Decommissioning Trust Funds | The following table summarizes the fair value of the fixed income securities held in nuclear decommissioning trust funds by contractual maturity:
| September 30, 2025
| (In millions)
Due within one year | $ | 19 |
Due after one through five years | 91 |
Due after five through ten years | 121 |
Due after ten years | 350 |
| $ | 581 |

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