Share-Based Payments - Additional Information (Detail) $ in Millions	Jan. 31, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation related to stock options	$ 0.1
Unrecognized compensation cost related to non-vested shares	$ 0.4

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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