Restructuring Charges- Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended	33 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2011 position	Jun. 30, 2014
Streamlining Actions
Restructuring Cost and Reserve [Line Items]
Net additional charges (net recovery/gain)	$ 53	$ 125
Net additional charges (net recovery/gain)	53	125
Operational Efficiency Initiatives 2011
Restructuring Cost and Reserve [Line Items]
Net additional charges (net recovery/gain)	4	(5)	107	38
Estimated reduction in workforce due to restructuring (positions)			1,500
Severance | Operational Efficiency Initiatives 2011
Restructuring Cost and Reserve [Line Items]
Net additional charges (net recovery/gain)	4		78	95
Other | Operational Efficiency Initiatives 2011
Restructuring Cost and Reserve [Line Items]
Net additional charges (net recovery/gain)	0			(57)
Operating lease and consulting costs | Operational Efficiency Initiatives 2011
Restructuring Cost and Reserve [Line Items]
Net additional charges (net recovery/gain)			29
Maximum | Operational Efficiency Initiatives 2011
Restructuring Cost and Reserve [Line Items]
Net additional charges (net recovery/gain)	$ 4