Condensed Consolidated Statements Of Cash Flows (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Apr. 30, 2013	Apr. 30, 2012
Cash flows from operating activities:
Consolidated net income	$ 3,945	$ 3,894
Adjustments to reconcile consoliated net income to net cash provided by operating activities:
Depreciation and amortization	2,194	2,106
Deferred income taxes	128	(149)
Other operating activities	(370)	(413)
Changes in certain assets and liabilities:
Receivables, net	567	494
Inventories	584	(150)
Accounts payable	(743)	(21)
Accrued liabilities	(1,527)	(1,714)
Accrued income taxes	116	1,387
Net cash provided by operating activities	4,894	5,434
Cash flows from investing activities:
Payments for property and equipment	(2,968)	(2,375)
Proceeds from the disposal of property and equipment	35	50
Other investing activities	(63)	(111)
Net cash used in investing activities	(2,996)	(2,436)
Cash flows from financing activities:
Net change in short-term borrowings	(551)	1,763
Proceeds from issuance of long-term debt	4,977	5
Payments of long-term debt	(1,088)	(545)
Dividends paid	(1,549)	(1,352)
Purchase of Company stock	(2,246)	(1,589)
Other financing activities	(284)	(89)
Net cash used in financing activities	(741)	(1,807)
Effect of exchange rates on cash and cash equivalents	(83)	376
Net increase in cash and cash equivalents	1,074	1,567
Cash and cash equivalents at beginning of year	7,781	6,550
Cash and cash equivalents at end of period	$ 8,855	$ 8,117