Income Taxes (Schedule Of Changes In Unrecognized Tax Benefits) (Details) (USD $) In Millions	12 Months Ended
Jan. 31, 2011	Jan. 31, 2010	Jan. 31, 2009
Income Taxes
Unrecognized tax benefits at beginning of year	$ 44	$ 31	$ 53
Additions for tax positions related to current year	1	10	9
Additions for tax positions related to prior years	1	9	5
Reductions for tax positions related to prior years	(8)	(1)	(5)
Settlements with taxing authorities	(12)		(30)
Lapse of statute of limitations	(3)	(5)	(1)
Unrecognized tax benefits at end of year	23	44	31
Unrecognized tax benefits that, if recognized, would affect the effective income tax rate	$ 17	$ 36	$ 23

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

+ References

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

+ References

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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