Property, Plant and Equipment - Schedule of Depreciation, Amortization, Accretion, and Depletion (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 23,740	$ 28,099	$ 49,340	$ 56,165
Depletion expense	93	1,734	93	1,946
Amortization expense	254	284	507	568
Accretion expense	29	28	58	42
Depreciation, depletion, amortization and accretion	$ 24,116	$ 30,145	$ 49,998	$ 58,721