ROYALTY AGREEMENT, UNALLOCATED RESERVE AND DISTRIBUTIONS (Details) - USD ($)		3 Months Ended		6 Months Ended
	Jul. 14, 2016	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2016	Jul. 31, 2015	Jan. 31, 2016
ROYALTY AGREEMENT, UNALLOCATED RESERVE AND DISTRIBUTIONS
Distributions declared per unit (in dollars per unit)		$ 0.2000	$ 0.0400	$ 0.4000	$ 0.0400
Unallocated Cash and Securities portion of Unallocated Reserve
Cash and U.S. Government securities		$ 6,817,915		$ 6,817,915		$ 8,783,882
Distribution payable		(2,624,002)		(2,624,002)		(656,001)
Unallocated cash and U.S. Government securities		4,193,913		4,193,913		$ 8,127,881
Reconciliation of Trust's Unallocated Reserve
Unallocated Reserve at the beginning of the period				8,989,164
Net loss		2,420,247	$ 2,483,644	1,989,995	$ 3,423,910
Distributions declared				(5,248,004)
Unallocated Reserve at the end of the period		$ 5,731,155		$ 5,731,155
Northshore
ROYALTY AGREEMENT, UNALLOCATED RESERVE AND DISTRIBUTIONS
Distributions declared per unit (in dollars per unit)	$ 0.20