Leases (Schedule of Future Minimum Lease Commitments and Sublease Receipts under Non-Cancelable Operating Leases) (Detail) (USD $) In Millions, unless otherwise specified	Jan. 31, 2014
Operating lease Commitment
2015	$ 95
2016	91
2017	76
2018	64
2019	53
2020 and thereafter	109
Total	488
Sublease receipts
2015	7
2016	7
2017	7
2018	5
2019	4
2020 and thereafter	12
Total	$ 42