XML 106 R78.htm IDEA: XBRL DOCUMENT v3.10.0.1
Significant Events - Kent Hills 3 Wind Project (Details) - Kent Hills 3 Wind Project - MW
12 Months Ended
Oct. 19, 2018
Dec. 31, 2018
Dec. 31, 2017
Investment [Line Items]      
Increase in contractual power capacity (in megawatts) 167 167  
New Brunswick Power Corporation      
Investment [Line Items]      
Capacity of facility (in megawatts)     17.25