Operating Segments - Disclosure of Reconciliation of Segment Revenue to Profit or Loss and Other Comprehensive Income (Details) - NZD ($) $ in Thousands	12 Months Ended
Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Disclosure Of Detailed information about reserves within equity [Text Block]
Total segment revenue	$ 104,153	$ 136,842	$ 156,311
Intersegment eliminations	(14,088)	(24,922)	(24,923)
Other revenue
Total revenue	$ 90,065	$ 111,920	$ 131,388

Expiry date 2020-01-01: The income arising in the course of an entity's ordinary activities. Income is increases in economic benefits during the accounting period in the form of inflows or enhancements of assets or decreases of liabilities that result in an increase in equity, other than those relating to contributions from equity participants. Effective 2020-01-01: The income arising in the course of an entity's ordinary activities. Income is increases in assets, or decreases in liabilities, that result in increases in equity, other than those relating to contributions from holders of equity claims.

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+ Details