Quarterly report pursuant to Section 13 or 15(d)

INVESTMENTS AND RESTRICTED CASH - Additional Information (Detail)

v3.2.0.727
INVESTMENTS AND RESTRICTED CASH - Additional Information (Detail) - USD ($)
$ in Millions
6 Months Ended 12 Months Ended
Jun. 30, 2015
Dec. 31, 2014
Gain (Loss) on Investments [Line Items]    
Trading Securities $ 2,007 $ 430
Restricted Cash and Investments, Noncurrent $ 469 $ 489
Fair Value Inputs, Discount Rate 8.29% 7.81%
cash held in escrow [Member]    
Gain (Loss) on Investments [Line Items]    
Restricted Cash and Cash Equivalents, Noncurrent $ 8 $ 28
Self-insurance requirements [Member]    
Gain (Loss) on Investments [Line Items]    
Restricted Cash and Investments, Noncurrent 442 442
Variable life insurance policy    
Gain (Loss) on Investments [Line Items]    
Restricted Cash and Investments, Noncurrent $ 19 $ 19