SAN ONOFRE NUCLEAR GENERATING STATION (SONGS) (Tables)

12 Months Ended

Dec. 31, 2017

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, 2017:
Debt securities:
Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies(1)	$	54	$	—	$	—		$	54
Municipal bonds(1)	245		7		(2		)	250
Other securities(2)	215		3		(1		)	217
Total debt securities	514		10		(3		)	521
Equity securities	171		326		(1		)	496
Cash and cash equivalents	16		—		—			16
Total	$	701	$	336	$	(4	)	$	1,033
At December 31, 2016:
Debt securities:
Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies	$	52	$	—	$	—		$	52
Municipal bonds	203		4		(1		)	206
Other securities	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

⁽¹⁾  Maturity dates are 2018-2048.

⁽²⁾  Maturity dates are 2018-2064.

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,
	2017			2016			2015
Proceeds from sales(1)	$	1,314		$	1,134		$	577
Gross realized gains	157			111			29
Gross realized losses	(14		)	(29		)	(15		)

⁽¹⁾  Excludes securities that are held to maturity.