Income Taxes Schedule of Changes in Unrecognized Tax Position (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Disclosure Schedule of Changes in Unrecognized Tax Position [Abstract]
Unrecognized tax benefits	$ 39,771us-gaap_UnrecognizedTaxBenefits	$ 31,321us-gaap_UnrecognizedTaxBenefits	$ 38,782us-gaap_UnrecognizedTaxBenefits
Gross increases-tax positions in prior period	7,022	3,863
Gross decreases-tax positions in prior period	(279)	(10,313)
Gross increases-tax positions in current period	4,904	3,900
Settlements	(126)	(1,581)
Lapse of statute of limitations	(2,709)	(2,982)
Unrecognized Tax Benefits, Decrease Resulting from Foreign Currency Translation	$ (362)	$ (348)

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

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Amount of decrease in unrecognized tax benefits resulting from foreign currency translation.

+ References

No definition available.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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