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v3.20.2

Fair Value of Derivative and Other Financial Instruments - Available for Sale Securities (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Debt securities, available-for-sale, unrealized loss position | $ 0 |  | $ 0 |  |
Other than temporary impairments |  |  | 0 |  |
PNM |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
(Increase)/decrease in other than temporary losses of available-for-sale securities, net portion recognized in earnings | 4,000,000.0 | $ (800,000) | (8,700,000) | $ 2,600,000 |
Proceeds from sales | 205,296,000 | 159,551,000 | 354,651,000 | 234,011,000 |
Gross realized gains | 11,262,000 | 10,906,000 | 17,087,000 | 15,095,000 |
Gross realized (losses) | (7,002,000) | $ (5,802,000) | (14,037,000) | $ (8,972,000) |
Recurring | PNM |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Available-for-sale debt securities | 389,452,000 |  | 389,452,000 |  | $ 388,832,000
Nuclear Decommissioning Trust | Recurring | PNM |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Available-for-sale debt securities | 335,500,000 |  | 335,500,000 |  | 336,000,000.0
Mine Reclamation Trust | Recurring | PNM |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Available-for-sale debt securities | $ 53,900,000 |  | $ 53,900,000 |  | $ 52,800,000

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