Notes Payable (Details) - USD ($) $ in Thousands	Jul. 31, 2015	Jan. 31, 2015
Debt Instrument
Notes Payable	$ 236,825	$ 230,400
Notes Payable, Noncurrent	3,188	230,400
4.00% Debentures due 2031
Debt Instrument
Notes Payable	233,637	230,400
Notes Payable, Current	233,637	0
Notes Payable, Other Payables
Debt Instrument
Notes Payable	$ 3,188	$ 0

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No definition available.

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- Definition

Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Publisher FASB

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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- Definition

Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20)

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