Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements - Narrative (Details)

v3.19.3.a.u2
Fair Value Measurements - Narrative (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Asset retirement obligation capitalized $ 5,935 $ 1,827
Asset retirement obligation, revised 948 $ (375)
Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Asset retirement obligation capitalized 5,900  
Asset retirement obligation, revised $ 900