XML 29 R71.htm IDEA: XBRL DOCUMENT v2.4.0.8
Fair Value Measurements - Additional Information (Detail) (USD $)
In Billions, unless otherwise specified
Sep. 30, 2014
Dec. 31, 2013
Sep. 30, 2013
Financial Instruments [Line Items]      
Estimated fair value of long-term debt, including the current portion $ 2.19 $ 1.62 $ 1.69
Long-term debt $ 2.10 $ 1.60 $ 1.65