XML 52 R40.htm IDEA: XBRL DOCUMENT v3.19.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)
 12 Months Ended
Jan. 31, 2019
USD ($)
Jan. 31, 2018
USD ($)
Jan. 31, 2017
USD ($)
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Number Of Operating Entities 5    
Number of Reportable Segments 2 2  
Concentration Risk, Customer   Six  
Property, Plant and Equipment, Depreciation Methods Depreciation is computed using the straight-line method.    
Depreciation $ 24,828,000 $ 21,462,000 $ 19,519,000
Liabilities   121,000  
Assets $ 471,393,000 $ 478,864,000  
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent 21.00% 33.80% 35.00%
Cost of Sales [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Maximum Percentage of Equity Ownership Interest Which May be Considered for Equity Method of Accounting 20.00%    
Contracts Not Accounted For Under Normal Purchases and Normal Sales      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Liabilities $ 21,000    
Assets   $ 100,000  
Minimum [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Operating Lease, Right-of-Use Asset $ 18,000,000    
Minimum [Member] | Building and Building Improvements [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Property, Plant and Equipment, Estimated Useful Lives 5    
Minimum [Member] | Fixtures And Equipment [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Property, Plant and Equipment, Estimated Useful Lives 2    
Maximum [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Operating Lease, Right-of-Use Asset $ 22,000,000    
Maximum [Member] | Building and Building Improvements [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Property, Plant and Equipment, Estimated Useful Lives 40 years    
Maximum [Member] | Fixtures And Equipment [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Property, Plant and Equipment, Estimated Useful Lives 20 years    
Customer Concentration Risk [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Concentration Risk, Customer Six   five
Concentration Risk, Percentage 85.00% 87.00% 83.00%
Income Tax Examination, Penalties and Interest Accrued $ 0.80 $ 0.89  
Accounting Standards Update 2016-18 [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Increase in Restricted Cash 354,000 130,000  
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect   224,000 $ 76,000
Refined Coal [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Assets $ 8,625,000 $ 12,165,000  
Refined Coal [Member] | Majority-Owned Subsidiary, Unconsolidated [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Number of Reportable Segments 1    
Consolidated Entities [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Number Of Operating Entities 4    
Equity Method Investee [Member]      
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]      
Number Of Operating Entities 1