Nuclear Decommissioning Trusts (Tables)

9 Months Ended

Sep. 30, 2013

Nuclear Decommissioning Trusts

Fair value of APS's nuclear decommissioning trust fund assets

The following table includes the unrealized gains and losses based on the original cost of the investment and summarizes the fair value of APS’s nuclear decommissioning trust fund assets at September 30, 2013 and December 31, 2012 (dollars in millions):

	Fair Value			Total Unrealized Gains		Total Unrealized Losses
September 30, 2013
Equity securities	$	245		$	104	$	—
Fixed income securities	371			13		(5		)
Net payables (a)	(3		)	—		—
Total	$	613		$	117	$	(5	)

(a) Net payables relate to pending securities sales and purchases.

	Fair Value			Total Unrealized Gains		Total Unrealized Losses
December 31, 2012
Equity securities	$	204		$	67	$	—
Fixed income securities	371			24		—
Net payables (a)	(4		)	—		—
Total	$	571		$	91	$	—

(a) Net payables relate to pending securities sales and purchases.

Realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds

The following table sets forth approximate realized gains and losses and proceeds from the sale of securities by the nuclear decommissioning trust funds (dollars in millions):

	Three Months Ended September 30,						Nine Months Ended September 30,
	2013			2012			2013			2012
Realized gains	$	1		$	1		$	4		$	5
Realized losses	(3		)	(1		)	(5		)	(3		)
Proceeds from the sale of securities (a)	110			84			364			295

(a) Proceeds are reinvested in the trust.

Fair value of fixed income securities, summarized by contractual maturities

The fair value of fixed income securities, summarized by contractual maturities, at September 30, 2013 is as follows (dollars in millions):

	Fair Value
Less than one year	$	12
1 year - 5 years	106
5 years - 10 years	104
Greater than 10 years	149
Total	$	371