New Accounting Standards (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 31, 2017	Jul. 31, 2017
Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unrecognized excess tax benefits reversed	$ 172	$ 172

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Balance Type:	na
Period Type:	duration