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Nuclear Decommissioning Trusts (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015 | Dec. 31, 2015
Nuclear decommissioning trust fund assets |  |  |  |  |
Fair Value | $ 767,416 |  | $ 767,416 |  | $ 735,196
Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds |  |  |  |  |
Proceeds from the sale of securities |  |  | 290,594 | $ 225,779 |
Fair value of fixed income securities, summarized by contractual maturities |  |  |  |  |
Total | 767,416 |  | 767,416 |  | 735,196
Arizona Public Service Company |  |  |  |  |
Nuclear decommissioning trust fund assets |  |  |  |  |
Fair Value | 767,416 |  | 767,416 |  | 735,196
Unrealized Gains | 188,879 |  | 188,879 |  | 169,053
Unrealized Losses | (352) |  | (352) |  | (2,760)
Net payables for securities purchases | (13,139) |  | (13,139) |  | (335)
Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds |  |  |  |  |
Realized gains | 2,282 | $ 1,260 | 4,720 | 2,455 |
Realized losses | (1,350) | (1,525) | (3,136) | (2,050) |
Proceeds from the sale of securities | 148,785 | $ 110,498 | 290,594 | $ 225,779 |
Fair value of fixed income securities, summarized by contractual maturities |  |  |  |  |
Total | 767,416 |  | 767,416 |  | 735,196
Arizona Public Service Company | Equity Securities |  |  |  |  |
Nuclear decommissioning trust fund assets |  |  |  |  |
Fair Value | 328,037 |  | 328,037 |  | 314,957
Unrealized Gains | 165,926 |  | 165,926 |  | 157,098
Unrealized Losses | (7) |  | (7) |  | (115)
Fair value of fixed income securities, summarized by contractual maturities |  |  |  |  |
Total | 328,037 |  | 328,037 |  | 314,957
Arizona Public Service Company | Fixed income securities. |  |  |  |  |
Nuclear decommissioning trust fund assets |  |  |  |  |
Fair Value | 452,518 |  | 452,518 |  | 420,574
Unrealized Gains | 22,953 |  | 22,953 |  | 11,955
Unrealized Losses | (345) |  | (345) |  | (2,645)
Fair value of fixed income securities, summarized by contractual maturities |  |  |  |  |
Less than one year | 13,046 |  | 13,046 |  |
1 year - 5 years | 133,548 |  | 133,548 |  |
5 years - 10 years | 103,874 |  | 103,874 |  |
Greater than 10 years | 202,050 |  | 202,050 |  |
Total | $ 452,518 |  | $ 452,518 |  | $ 420,574

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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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