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Nuclear Decommissioning Trusts (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016 | Dec. 31, 2016
Nuclear decommissioning trust fund assets |  |  |  |  |
Fair Value | $ 822,244 |  | $ 822,244 |  | $ 779,586
Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds |  |  |  |  |
Proceeds from the sale of securities |  |  | 275,364 | $ 290,594 |
Fair value of fixed income securities, summarized by contractual maturities |  |  |  |  |
Total | 822,244 |  | 822,244 |  | 779,586
Arizona Public Service Company |  |  |  |  |
Nuclear decommissioning trust fund assets |  |  |  |  |
Fair Value | 822,244 |  | 822,244 |  | 779,586
Unrealized Gains | 229,512 |  | 229,512 |  | 197,911
Unrealized Losses | (2,630) |  | (2,630) |  | (4,962)
Net receivables for securities purchases | 1,833 |  | 1,833 |  | 795
Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds |  |  |  |  |
Realized gains | 939 | $ 2,282 | 3,306 | 4,720 |
Realized losses | (1,159) | (1,350) | (3,612) | (3,136) |
Proceeds from the sale of securities | 124,238 | $ 148,785 | 275,364 | $ 290,594 |
Fair value of fixed income securities, summarized by contractual maturities |  |  |  |  |
Total | 822,244 |  | 822,244 |  | 779,586
Arizona Public Service Company | Equity Securities |  |  |  |  |
Nuclear decommissioning trust fund assets |  |  |  |  |
Fair Value | 384,999 |  | 384,999 |  | 353,261
Unrealized Gains | 217,288 |  | 217,288 |  | 188,091
Unrealized Losses | 0 |  | 0 |  | 0
Fair value of fixed income securities, summarized by contractual maturities |  |  |  |  |
Total | 384,999 |  | 384,999 |  | 353,261
Arizona Public Service Company | Fixed income securities. |  |  |  |  |
Nuclear decommissioning trust fund assets |  |  |  |  |
Fair Value | 435,412 |  | 435,412 |  | 425,530
Unrealized Gains | 12,224 |  | 12,224 |  | 9,820
Unrealized Losses | (2,630) |  | (2,630) |  | (4,962)
Fair value of fixed income securities, summarized by contractual maturities |  |  |  |  |
Less than one year | 14,979 |  | 14,979 |  |
1 year – 5 years | 123,392 |  | 123,392 |  |
5 years – 10 years | 107,622 |  | 107,622 |  |
Greater than 10 years | 189,419 |  | 189,419 |  |
Total | $ 435,412 |  | $ 435,412 |  | $ 425,530

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- Definition The fair value of investments held in a trust fund to pay for the costs of decontaminating and decommissioning facilities, whether such amount is presented as a separate caption or as a parenthetical disclosure on the balance sheet. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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