Subsequent Events	3 Months Ended
Apr. 30, 2011
Subsequent Events [Abstract]
Subsequent Events	15. Subsequent Events We monitor significant events occurring after the balance sheet date and prior to the issuance of the financial statements to determine the impacts, if any, of events on the financial statements to be issued. All subsequent events of which we are aware have been evaluated. For information on subsequent event disclosure related to regulatory matters, see Note 2 to the consolidated financial statements in this Form 10-Q. On June 1, 2011, we redeemed all of the 6.25% insured quarterly notes with an aggregate principal balance of $196.8 million. We financed the debt redemption with short-term bank borrowings under the revolving syndicated credit facility. On June 6, 2011, we issued $40 million unsecured senior notes maturing in 2016 that bear an interest rate of 2.92% and $160 million unsecured senior notes maturing in 2021 that bear an interest rate of 4.24%. We used the proceeds from the sale of the senior notes to reduce our short-term borrowings as well as for other general corporate purposes and working capital needs.

Describes disclosed significant events or transactions that occurred after the balance sheet date, but before the issuance of the financial statements. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, losses resulting from fire or flood, losses on receivables, significant realized and unrealized gains and losses that result from changes in quoted market prices of securities, declines in market prices of inventory, changes in authorized or issued debt (SEC), significant foreign exchange rate changes, substantial loans to insiders or affiliates, significant long-term investments, and substantial dividends not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 11

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