FINANCIAL INSTRUMENTS (Tables)

12 Months Ended

Dec. 31, 2012

Notes To Financial Statements [Abstract]

Fair Value Measurement of Assets and Liabilities

The following financial instruments are recorded at their estimated fair value. The following table presents information about the fair value measurement of our assets and liabilities as of December 31, 2012 and 2011:

		As of December 31,
Financial Instruments Recorded at Fair Value on a Recurring Basis:	Fair Value Measurement Level	2012		2011
		(In millions)
Assets:
Cash and cash equivalents:
Bank deposits and certificates of deposit	1	$	240	$	225
Money market funds	1	6		7
Total cash and cash equivalents:		246		232
Restricted funds held in trust:
Bank deposits and certificates of deposit	1	2		5
Money market funds	1	64		119
U.S. Treasury/Agency obligations (1)	1	125		15
State and municipal obligations	1	11		7
Commercial paper/Guaranteed investment contracts/Repurchase agreements	1	12		45
Total restricted funds held in trust:		214		191
Restricted funds — other:
Bank deposits and certificates of deposit (2)(3)	1	5		5
Money market funds (3)	1	8		7
Residential mortgage-backed securities (3)	1	1		1
Total restricted funds other:		14		13
Investments:
Mutual and bond funds (2)	1	2		2
Investments available for sale:
U.S. Treasury/Agency obligations (4)	1	6		8
Residential mortgage-backed securities (4)	1	11		7
Other government obligations (4)	1	5		3
Corporate investments (4)	1	14		13
Equity securities (3)	1	3		1
Total investments:		41		34
Derivative Asset — Note Hedge	2	104		47
Derivative Asset — Energy Hedges	2	—		3
Total assets:		$	619	$	520
Liabilities:
Derivative Liability — Cash Conversion Option	2	$	105	$	49
Derivative Liabilities — Contingent interest features of the 3.25% Notes and Debentures	2	0		0
Derivative Liability — Energy Hedges	2	1		—
Total liabilities:		$	106	$	49

The following financial instruments are recorded at their carrying amount.

	As of December 31, 2012				As of December 31, 2011
Financial Instruments Recorded at Carrying Amount:	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Assets:
Accounts receivables (5)	$	283	$	283	$	277	$	277
Liabilities:
Long-term debt	$	2,015	$	2,081	$	1,486	$	1,470
Project debt	$	317	$	329	$	680	$	693

(1) The U.S. Treasury/Agency obligations in restricted funds held in trust are primarily comprised of Federal Home Loan Mortgage Corporation securities at fair value.

(2) Included in other noncurrent assets in the consolidated balance sheets.

(3) Included in prepaid expenses and other current assets in the consolidated balance sheets.

(4) Included in investments in fixed maturities at market in the consolidated balance sheets.

(5) Includes $27 million and $17 million of noncurrent receivables in other noncurrent assets in the consolidated balance sheets as of December 31, 2012 and 2011, respectively.

Expected Maturities of Fixed Maturity Securities by Amortized Cost and Fair Value

The expected maturities of fixed maturity securities, by amortized cost and fair value are shown below (in millions):

	As of December 31, 2012
	Amortized Cost		Fair Value
Available-for-sale:
One year or less	$	5	$	5
Over one year to five years	15		15
Over five years to ten years	16		16
More than ten years	—		—
Total fixed maturities	$	36	$	36

Temporarily Impaired Investments Held by Insurance Subsidiary

The following table sets forth a summary of temporarily impaired investments held by our insurance subsidiary (dollars in millions):

	As of December 31, 2012			As of December 31, 2011
Description of Investments	Fair Value		Number of Investments	Fair Value		Number of Investments
U.S. Treasury and other direct U.S. Government obligations	$	1	1	$	—	—
Residential mortgage-backed securities	9		12	4		5
Other government obligations	—		1	1		2
Corporate bonds	1		3	6		17
Total fixed maturities	11			11
Equity securities	1		8	—		6
Total temporarily impaired investments	$	12		$	11