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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)
12 Months Ended
Jan. 31, 2016
USD ($)
T
Jan. 31, 2015
USD ($)
Cash and Cash Equivalents    
Amount held by the Trust in a money market fund | $ $ 2,499,706 $ 8,717,943
Revenue Recognition    
Quantity of iron ore shipped by NMC subject to price determination recognized in revenue (in tons) | T 880,432  
Fixed Property, Including Intangibles    
Percentage of fee interest owned by Mesabi Land Trust in the lands subject to the Peters Lease 20.00%