Segment Information (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) item	Dec. 31, 2020 USD ($)
Assets held for sale	$ 216,197	$ 47,635
Property, plant and equipment, gross	2,879,065	2,576,870
Pumpco [Member]
Assets held for sale	$ 216,200	$ 47,600
Drilling Rig Service Line [Member]
Land based drilling rigs \| item	12
Property, plant and equipment, gross	$ 66,200
Proceeds from sale	78,000
Loss on sale of assets	200
Impairment	$ 7,500

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