Discontinued Operations (Assets And Liabilities of Disposal Groups) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total assets	$ 47,635	$ 216,197
Total current liabilities	4,079	44,938
Pumpco [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total assets	47,600	216,200
Pumpco [Member] | Discontinued Operations, Held-for-sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accounts receivable, net		25,106
Other current assets	2,155	6,215
Total current assets	2,155	31,321
Property, plant and equipment, net	45,397	179,144
Operating lease ROU assets	83	5,732
Total assets	47,635	216,197
Accounts payable	165	14,370
Accrued expenses	1,326	24,751
Total current liabilities	1,491	39,121
Operating lease liabilities	2,588	5,415
Other long-term liabilities		402
Total current liabilities	$ 4,079	$ 44,938