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COMMITMENTS AND CONTINGENCIES - Contingencies (Details)
Dec. 17, 2013
fatality
Dec. 31, 2015
site
Aug. 30, 2014
site
Laclede Gas      
Loss Contingencies [Line Items]      
Number of former manufactured gas plant (MGP) sites in Missouri   3  
Number of former manufactured gas plant (MGP) sites in Shrewsbury, Missouri   1  
Number of former manufactured gas plant (MGP) sites in the City of St. Louis   2  
Alagasco      
Loss Contingencies [Line Items]      
Number of former manufactured gas plant (MGP)   9  
Number of former manufactured gas distribution   5  
Number of incident fatalities | fatality 1    
Previous Ownership | Laclede Gas      
Loss Contingencies [Line Items]      
Number of former manufactured gas plant (MGP)     19
Previous Ownership | Missouri Gas Energy (MGE)      
Loss Contingencies [Line Items]      
Number of former manufactured gas plant (MGP)   7  
Current Ownership | Alagasco      
Loss Contingencies [Line Items]      
Number of former manufactured gas plant (MGP)   4  
Number of former manufactured gas distribution   1