Investments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2014 Patriot And Big River [Member]	Jan. 31, 2014 Patriot And Big River [Member]
Investments (Details) [Line Items]
Retained Earnings, Undistributed Earnings from Equity Method Investees	$ 35.9	$ 32.6
Proceeds from Equity Method Investment, Dividends or Distributions	5.0	0.2
Proportionate Share of Restricted Net Assets			$ 366.5	$ 366.2

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Proportionate share of restricted net assets as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Article 5

+ Details

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- Definition

Amount of consolidated retained earnings that represent undistributed (not yet received) earnings from 50% or less owned persons accounted for by the equity method (equity method investees).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 852

-SubTopic 20

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6462270&loc=d3e57205-112772

+ Details

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