v2.4.0.8
Income Taxes - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Income Tax Disclosure [Abstract]    
Effective Income Tax Rate Reconciliation, Percent 32.00% 28.00%
Tax benefit recognized related to CA apportionment rules   $ (76)
Unrecognized Tax Benefits, Period Increase (Decrease) 47  
Unrecognized Tax Benefits that Would Impact Effective Tax Rate, Period Increase (Decrease) 45  
Increase (decrease) In Unrecognized Tax Benefits, Penalties On Income Taxes Accrued $ 2 $ 2