Schedule of Supplementary Cash Flow Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2012
Supplemental Cash Flow Information [Abstract]
Decrease in accrued stock repurchases	$ 0	$ 0	$ (7)
Vested stock issued as settlement of annual accrued bonus	2	2	3
Stock issued in lieu of cash dividends	18	3	0
Capital lease obligations	1	0	2
Fair value of assets acquired in acquisitions	259	541	238
Cash paid in acquisitions, net of cash acquired of $0 million, $9 million and $5 million in fiscal 2014, 2013 and 2012, respectively	(3)	(483)	(218)
Forgiveness of accounts receivable to acquire equity interest in business combination	(105)	0	0
Accrued acquisition payables, net	(3)	(13)	0
Liabilities assumed in acquisitions	148	45	20
Cash paid for interest (including discontinued operations)	82	92	107
Cash paid for income taxes (including discontinued operations)	$ 63	$ 128	$ 289