v3.6.0.2

SAN ONOFRE NUCLEAR GENERATING STATION (SONGS) (Tables) | 12 Months Ended
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Dec. 31, 2016
Regulated Operations [Abstract] |
Schedule of Nuclear Decommissioning Trusts | The following table shows the fair values and gross unrealized gains and losses for the securities held in the NDT. We provide additional fair value disclosures for the NDT in Note 10.
NUCLEAR DECOMMISSIONING TRUSTS
(Dollars in millions)
| Cost |  | Gross unrealized gains |  | Gross unrealized losses |  | Estimated fair value
At December 31, 2016: |  |  |  |  |  |  |
Debt securities: |  |  |  |  |  |  |
Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies(1) | $ | 52 |  |  | $ | — |  |  | $ | — |  |  | $ | 52 |
Municipal bonds(2) | 203 |  |  | 4 |  |  | (1 | ) |  | 206 |
Other securities(3) | 141 |  |  | 2 |  |  | (2 | ) |  | 141 |
Total debt securities | 396 |  |  | 6 |  |  | (3 | ) |  | 399 |
Equity securities | 143 |  |  | 366 |  |  | (1 | ) |  | 508 |
Cash and cash equivalents | 119 |  |  | — |  |  | — |  |  | 119 |
Total | $ | 658 |  |  | $ | 372 |  |  | $ | (4 | ) |  | $ | 1,026 |
At December 31, 2015: |  |  |  |  |  |  |  |  |  |  |
Debt securities: |  |  |  |  |  |  |  |  |  |  |
Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies | $ | 89 |  |  | $ | 2 |  |  | $ | — |  |  | $ | 91 |
Municipal bonds | 148 |  |  | 8 |  |  | — |  |  | 156 |
Other securities | 194 |  |  | 1 |  |  | (13 | ) |  | 182 |
Total debt securities | 431 |  |  | 11 |  |  | (13 | ) |  | 429 |
Equity securities | 214 |  |  | 412 |  |  | (7 | ) |  | 619 |
Cash and cash equivalents | 15 |  |  | — |  |  | — |  |  | 15 |
Total | $ | 660 |  |  | $ | 423 |  |  | $ | (20 | ) |  | $ | 1,063 |
(1) | Maturity dates are 2017-2047.
(2) | Maturity dates are 2017-2115.
(3) | Maturity dates are 2017-2111.
Schedule of Securities Sold | The following table shows the proceeds from sales of securities in the NDT and gross realized gains and losses on those sales.
SALES OF SECURITIES
(Dollars in millions)
| Years ended December 31,
| 2016 |  | 2015 |  | 2014
Proceeds from sales(1) | $ | 1,134 |  |  | $ | 577 |  |  | $ | 601 |
Gross realized gains | 111 |  |  | 29 |  |  | 11 |
Gross realized losses | (29 | ) |  | (15 | ) |  | (11 | )
(1) | Excludes securities that are held to maturity.

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