Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation (Details)

v3.8.0.1
Basis of Presentation (Details)
a in Thousands, $ in Thousands
3 Months Ended 6 Months Ended
Mar. 31, 2018
USD ($)
a
classification
segment
Mar. 31, 2017
USD ($)
Mar. 31, 2018
USD ($)
a
classification
segment
Mar. 31, 2017
USD ($)
Property, Plant and Equipment [Line Items]        
Number of business segments | segment 3   3  
Ownership interest (as a percent) 51.00% 51.00% 51.00% 51.00%
Citree        
Property, Plant and Equipment [Line Items]        
Net income (loss) attributable to noncontrolling interest | $ $ (33) $ 104 $ (49) $ 88
Land        
Property, Plant and Equipment [Line Items]        
Area of land owned (in acres) 121   121  
Number of primary classifications | classification 2   2  
Mineral Rights        
Property, Plant and Equipment [Line Items]        
Area of land owned (in acres) 90   90