XML 39 R64.htm IDEA: XBRL DOCUMENT v3.20.1
Fair Value of Financial Instruments and Derivative Instruments Derivative Instruments (Details) - tonne
 1 Months Ended 12 Months Ended
Dec. 31, 2019
Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Bunker fuel, annual tonnes 12,000  
Bunker fuel, monthly tonnes 1,000  
Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Bunker fuel, sulphur content   0.50%
Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Bunker fuel, sulphur content   3.50%