NATURE OF BUSINESS AND ORGANIZATION (Details) - USD ($)		3 Months Ended
	Apr. 13, 2018	Apr. 30, 2018	Apr. 30, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Royalty income		$ 6,646,670	$ 4,760,429
Interest		37,377	6,542
Total revenues		6,684,047	4,766,971
Expenses		368,199	295,046
Net income		$ 6,315,848	$ 4,471,925
Number of units outstanding		13,120,010	13,120,010
Net income per unit (Note 2) (in dollars per unit)		$ 0.4814	$ 0.3408
Distributions declared per unit (Note 3) (in dollars per unit)	$ 0.45	$ 0.4500	$ 0.5500
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Royalty income			$ 1,110,218
Total revenues			1,110,218
Net income			$ 1,110,218
Number of units outstanding			13,120,010
Net income per unit (Note 2) (in dollars per unit)			$ 0.0846
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Royalty income			$ 3,650,211
Interest			6,542
Total revenues			3,656,753
Expenses			295,046
Net income			$ 3,361,707
Number of units outstanding			13,120,010
Net income per unit (Note 2) (in dollars per unit)			$ 0.2562
Distributions declared per unit (Note 3) (in dollars per unit)			$ 0.5500