Income Taxes - Unrecognized Tax Benefits Excluding Potential Penalties and Interest (Detail) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Income Tax Disclosure [Abstract]
Unrecognized tax benefits as of beginning of year		$ 92	$ 254
Increases as a result of tax positions taken in prior years	$ 0	0	0
Increases as a result of tax positions taken in current year	$ 0	0	0
Settlements		(44)	(162)
Lapse of statute of limitations		$ (48)
Unrecognized tax benefits as of end of year			$ 92

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- Definition

Amount of unrecognized tax benefits.

+ 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=65882285&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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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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