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Regulatory Matters - Schedule of Regulatory Assets (Details) - USD ($) $ in Thousands | Mar. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Detail of regulatory assets |  |
Regulatory assets, current | $ 155,941 | $ 106,875
Regulatory assets, non-current | 1,321,473 | 1,313,428
Pension |  |
Detail of regulatory assets |  |
Regulatory assets, current | 0 | 0
Regulatory assets, non-current | 699,817 | 711,059
Retired power plant costs |  |
Detail of regulatory assets |  |
Regulatory assets, current | 9,913 | 9,913
Regulatory assets, non-current | 115,110 | 117,591
Income taxes — allowance for funds used during construction (AFUDC) equity |  |
Detail of regulatory assets |  |
Regulatory assets, current | 6,202 | 6,305
Regulatory assets, non-current | 150,629 | 152,118
Deferred fuel and purchased power — mark-to-market (Note 6) |  |
Detail of regulatory assets |  |
Regulatory assets, current | 30,203 | 0
Regulatory assets, non-current | 59,428 | 42,963
Deferred fuel and purchased power (b) (e) |  |
Detail of regulatory assets |  |
Regulatory assets, current | 17,625 | 12,465
Regulatory assets, non-current | 0 | 0
Four Corners cost deferral |  |
Detail of regulatory assets |  |
Regulatory assets, current | 6,689 | 6,689
Regulatory assets, non-current | 55,221 | 56,894
Income taxes — investment tax credit basis adjustment |  |
Detail of regulatory assets |  |
Regulatory assets, current | 2,120 | 2,120
Regulatory assets, non-current | 54,265 | 54,356
Lost fixed cost recovery (b) |  |
Detail of regulatory assets |  |
Regulatory assets, current | 70,762 | 61,307
Regulatory assets, non-current | 0 | 0
Palo Verde VIEs (Note 5) |  |
Detail of regulatory assets |  |
Regulatory assets, current | 0 | 0
Regulatory assets, non-current | 18,930 | 18,775
Deferred compensation |  |
Detail of regulatory assets |  |
Regulatory assets, current | 0 | 0
Regulatory assets, non-current | 36,846 | 35,595
Deferred property taxes |  |
Detail of regulatory assets |  |
Regulatory assets, current | 0 | 0
Regulatory assets, non-current | 79,447 | 73,200
Loss on reacquired debt |  |
Detail of regulatory assets |  |
Regulatory assets, current | 1,637 | 1,637
Regulatory assets, non-current | 16,533 | 16,942
Tax expense of Medicare subsidy |  |
Detail of regulatory assets |  |
Regulatory assets, current | 1,503 | 1,513
Regulatory assets, non-current | 10,458 | 10,589
Demand side management (b) |  |
Detail of regulatory assets |  |
Regulatory assets, current | 5,491 | 3,744
Regulatory assets, non-current | 0 | 0
AG-1 deferral |  |
Detail of regulatory assets |  |
Regulatory assets, current | 0 | 0
Regulatory assets, non-current | 6,976 | 5,868
Mead-Phoenix transmission line CIAC |  |
Detail of regulatory assets |  |
Regulatory assets, current | 332 | 332
Regulatory assets, non-current | 10,625 | 10,708
Transmission cost adjustor (b) |  |
Detail of regulatory assets |  |
Regulatory assets, current | 2,071 | 0
Regulatory assets, non-current | 2,460 | 1,588
Coal reclamation |  |
Detail of regulatory assets |  |
Regulatory assets, current | 418 | 418
Regulatory assets, non-current | 4,728 | 5,182
Other |  |
Detail of regulatory assets |  |
Regulatory assets, current | 975 | 432
Regulatory assets, 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://www.xbrl.org/2003/role/presentationRef -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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