Significant Accounting Policies - Fair Value of Liabilities (Details) - USD ($)	Jan. 31, 2019	Jan. 31, 2018
Fair Value, Liabilities Measured on Recurring Basis
Royalty liability	$ 905,000	$ 2,469,000
Significant Unobservable Inputs (Level 3)
Fair Value, Liabilities Measured on Recurring Basis
Royalty liability	$ 905,000	$ 2,469,000

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.

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