Discontinued Operations (Components Of Income (Loss) From Discontinued Operations) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss from discontinued operations, net of income tax	$ (47,129)	$ (15,061)
Pumpco [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	254	101,902
Cost of services	5,459	90,110
Loss from discontinued operations before tax	(59,651)	(17,037)
Loss from discontinued operations, net of income tax	$ 47,129	$ (15,061)