Annual report pursuant to Section 13 and 15(d)

CASH AND INVESTMENTS - Additional Information (Detail)

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CASH AND INVESTMENTS - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended 3 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Jun. 30, 2011
Mortgage and asset-backed debt securities
Dec. 31, 2012
Self-insurance requirements
Dec. 31, 2011
Self-insurance requirements
Dec. 31, 2012
Variable life insurance policy
Dec. 31, 2011
Variable life insurance policy
Gain (Loss) on Investments [Line Items]                
Gross realized gains on sales of marketable securities $ 15 $ 49 $ 24          
Gross realized losses on sales of marketable securities 6 20 18          
Impairment charge 0 0 21 21        
Auction rate securities at carrying value       128        
Auction rate securities fair value       107        
Investments and Restricted Cash $ 307 $ 303     $ 288 $ 286 $ 19 $ 17
Weighted average discount rate 7.75% 7.91%