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Regulatory Matters - Schedule of Regulatory Assets (Details) - USD ($) $ in Thousands | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Detail of regulatory assets |  |
Current | $ 251,594 | $ 203,207
Non-Current | 1,315,846 | 1,304,073
Pension |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 663,327 | 660,223
Income taxes — allowance for funds used during construction (AFUDC) equity |  |
Detail of regulatory assets |  |
Current | 6,815 | 6,800
Non-Current | 156,528 | 154,974
Retired power plant costs |  |
Detail of regulatory assets |  |
Current | 28,182 | 28,182
Non-Current | 128,304 | 142,503
Deferred fuel and purchased power |  |
Detail of regulatory assets |  |
Current | 101,425 | 70,137
Non-Current | 0 | 0
Deferred fuel and purchased power — mark-to-market (Note 7) |  |
Detail of regulatory assets |  |
Current | 42,911 | 36,887
Non-Current | 26,151 | 33,185
Ocotillo deferral |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 65,571 | 38,144
SCR deferral |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 64,971 | 52,644
Deferred property taxes |  |
Detail of regulatory assets |  |
Current | 8,569 | 8,569
Non-Current | 53,911 | 58,196
Deferred compensation |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 36,481 | 36,464
Four Corners cost deferral |  |
Detail of regulatory assets |  |
Current | 8,077 | 8,077
Non-Current | 28,113 | 32,152
Lost fixed cost recovery |  |
Detail of regulatory assets |  |
Current | 34,144 | 26,067
Non-Current | 0 | 0
Income taxes — investment tax credit basis adjustment |  |
Detail of regulatory assets |  |
Current | 1,098 | 1,098
Non-Current | 24,532 | 24,981
Palo Verde VIEs (Note 6) |  |
Detail of regulatory assets |  |
Current | 0 | 0
Non-Current | 20,945 | 20,635
Coal reclamation |  |
Detail of regulatory assets |  |
Current | 1,068 | 1,546
Non-Current | 17,533 | 17,688
Loss on reacquired debt |  |
Detail of regulatory assets |  |
Current | 1,637 | 1,637
Non-Current | 11,241 | 12,031
TCA balancing account |  |
Detail of regulatory assets |  |
Current | 8,272 | 6,324
Non-Current | 2,926 | 2,885
Mead-Phoenix transmission line contributions in aid of construction (CIAC) |  |
Detail of regulatory assets |  |
Current | 332 | 332
Non-Current | 9,546 | 9,712
Tax expense of Medicare subsidy |  |
Detail of regulatory assets |  |
Current | 1,238 | 1,235
Non-Current | 4,444 | 4,940
AG-1 deferral |  |
Detail of regulatory assets |  |
Current | 2,787 | 2,787
Non-Current | 1,322 | 2,716
Tax expense adjustor mechanism |  |
Detail of regulatory assets |  |
Current | 3,640 | 1,612
Non-Current | 0 | 0
Other |  |
Detail of regulatory assets |  |
Current | 1,399 | 1,917
Non-Current | $ 0 | $ 0

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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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