Income Taxes Schedule of Changes in Unrecognized Tax Position (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Disclosure Schedule of Changes in Unrecognized Tax Position [Abstract]
Unrecognized tax benefits	$ 48,674	$ 39,771	$ 31,321
Gross increases-tax positions in prior period	6,548	7,022
Gross decreases-tax positions in prior period	(1,702)	(279)
Gross increases-tax positions in current period	6,509	4,904
Settlements	0	(126)
Lapse of statute of limitations	(1,125)	(2,709)
Unrecognized tax benefits, decrease resulting from foreign currency translation	$ (1,327)	$ (362)

Disclosure Schedule of Changes in Unrecognized Tax Position [Abstract]

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- Definition

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
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

Reference 2: 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

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- Definition

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

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Amount of decrease 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 settlements with taxing authorities.

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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.

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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.

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