Investments

12 Months Ended

Dec. 31, 2012

Investments

Investments

5. Investments

The following table summarizes our short-term and long-term investments at December 31, 2012and 2011(amounts in millions):

				Amortized		Gross unrealized		Gross unrealized		Fair
At December 31, 2012				cost		gains		losses		Value
Short-term investments:
	Available-for-sale investments:
		U.S. treasuries and government agency
			securities	$	387	$	---	$	---	$	387
		Corporate bonds			11		---		---		11
	Restricted cash										18
Total short-term investments										$	416
Long-term investments:
	Available-for-sale investments:
		Auction rate securities held through Morgan
			Stanley Smith Barney LLC	$	8	$	---	$	---	$	8
				Amortized		Gross unrealized		Gross unrealized		Fair
At December 31, 2011				cost		gains		losses		Value
Short-term investments:
	Available-for-sale investments:
		U.S. treasuries and government agency
			securities	$	344	$	---	$	---	$	344
	Restricted cash										16
Total short-term investments										$	360
Long-term investments:
	Available-for-sale investments:
		Auction rate securities held through Morgan
			Stanley Smith Barney LLC	$	17	$	---	$	(1)	$	16

The following table illustrates the gross unrealized losses on available-for-sale securities, the fair value of those securities, aggregated by investment categories, and the length of time that they have been in a continuous unrealized loss position at December 31, 2011 (amounts in millions):

	Less than 12 months				12 months or more				Total
	Unrealized		Fair		Unrealized		Fair		Unrealized		Fair
At December 31, 2011	losses		Value		losses		Value		losses		Value
Taxable auction rate securities	$	---	$	---	$	(1)	$	16	$	(1)	$	16

The following table summarizes the contractually stated maturities of our short-term and long-term investments classified as available-for-sale at December 31, 2012 (amounts in millions):

	Amortized		Fair
At December 31, 2012	cost		Value
U.S. government agency securities and corporate bonds
due in 1 year or less	$	398	$	398
Auction rate securities due after ten years		8		8
	$	406	$	406