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Regulatory Matters - Schedule of Regulatory Assets (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Detail of regulatory assets |  |
Current | $ 225,471 | $ 203,207
Non-Current | 1,302,448 | 1,304,073
Pension |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 652,691 | 660,223
Retired power plant costs |  |
Detail of regulatory assets |  |
Current | 28,182 | 28,182
Non-Current | 135,349 | 142,503
Income taxes — allowance for funds used during construction (AFUDC) equity |  |
Detail of regulatory assets |  |
Current | 6,815 | 6,800
Non-Current | 155,369 | 154,974
Deferred fuel and purchased power — mark-to-market (Note 7) |  |
Detail of regulatory assets |  |
Current | 51,954 | 36,887
Non-Current | 32,576 | 33,185
Deferred fuel and purchased power |  |
Detail of regulatory assets |  |
Current | 77,730 | 70,137
Non-Current | 0 | 0
Deferred property taxes |  |
Detail of regulatory assets |  |
Current | 8,569 | 8,569
Non-Current | 56,053 | 58,196
SCR deferral |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 58,258 | 52,644
Ocotillo deferral |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 51,767 | 38,144
Four Corners cost deferral |  |
Detail of regulatory assets |  |
Current | 8,077 | 8,077
Non-Current | 30,133 | 32,152
Deferred compensation |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 37,550 | 36,464
Lost fixed cost recovery |  |
Detail of regulatory assets |  |
Current | 28,885 | 26,067
Non-Current | 0 | 0
Income taxes — investment tax credit basis adjustment |  |
Detail of regulatory assets |  |
Current | 1,098 | 1,098
Non-Current | 24,920 | 24,981
Palo Verde VIEs (Note 6) |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 20,790 | 20,635
Coal reclamation |  |
Detail of regulatory assets |  |
Current | 1,068 | 1,546
Non-Current | 17,800 | 17,688
Loss on reacquired debt |  |
Detail of regulatory assets |  |
Current | 1,637 | 1,637
Non-Current | 11,636 | 12,031
Mead-Phoenix transmission line contributions in aid of construction (CIAC) |  |
Detail of regulatory assets |  |
Current | 332 | 332
Non-Current | 9,629 | 9,712
TCA balancing account |  |
Detail of regulatory assets |  |
Current | 6,048 | 6,324
Non-Current | 1,027 | 2,885
Tax expense of Medicare subsidy |  |
Detail of regulatory assets |  |
Current | 1,238 | 1,235
Non-Current | 4,881 | 4,940
AG-1 deferral |  |
Detail of regulatory assets |  |
Current | 2,787 | 2,787
Non-Current | 2,019 | 2,716
Tax expense adjustor mechanism |  |
Detail of regulatory assets |  |
Current | 942 | 1,612
Non-Current | 0 | 0
Other |  |
Detail of regulatory assets |  |
Current | 109 | 1,917
Non-Current | $ 0 | $ 0

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