Quarterly report pursuant to Section 13 or 15(d)

Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)

v3.20.1
Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - Recurring - USD ($)
$ in Thousands
Mar. 31, 2020
Dec. 31, 2019
Assets:    
Derivative contracts $ 10,604 $ 3,928
Restoration plan assets 3,435 4,199
Total 14,039 8,127
Liabilities:    
Derivative contracts 5,217 12,415
Quoted Prices in Active Markets (Level 1)     
Assets:    
Derivative contracts 0 0
Restoration plan assets 3,435 4,199
Total 3,435 4,199
Liabilities:    
Derivative contracts 0 0
Significant Other Observable Inputs (Level 2)    
Assets:    
Derivative contracts 10,604 3,928
Restoration plan assets 0 0
Total 10,604 3,928
Liabilities:    
Derivative contracts 5,217 12,415
Significant Unobservable Inputs (Level 3)    
Assets:    
Derivative contracts 0 0
Restoration plan assets 0 0
Total 0 0
Liabilities:    
Derivative contracts $ 0 $ 0