Summary Of Significant Accounting Policies (Summary Of Activity Of Goodwill) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Beginning Balance		$ 136,788	$ 807,860
Foreign currency translation adjustments		907	(2,234)
Reduction in value of assets	[1]		(668,838)
Ending Balance		137,695	136,788
Drilling Products And Services [Member]
Goodwill [Roll Forward]
Beginning Balance		136,788	138,493
Foreign currency translation adjustments		907	(1,705)
Ending Balance		$ 137,695	136,788
Onshore Completion And Workover Services [Member]
Goodwill [Roll Forward]
Beginning Balance			583,550
Reduction in value of assets	[1]		(583,550)
Production Services [Member]
Goodwill [Roll Forward]
Beginning Balance			85,817
Foreign currency translation adjustments			(529)
Reduction in value of assets	[1]		$ (85,288)

[1] Onshore Drilling Completion Products and Workover Production and Services Services Services Total Balance, December 31, 2017 $ 138,493 $ 583,550 $ 85,817 $ 807,860 Foreign currency translation adjustment (1,705) - (529) (2,234) Reduction in value of assets - (583,550) ⁽¹⁾ (85,288) (668,838) Balance, December 31, 2018 136,788 - - 136,788 Foreign currency translation adjustment 907 - - 907 Balance, December 31, 2019 $ 137,695 $ - $ - $ 137,695 (1)$417.0 million of reduction in value of assets was allocated to Pumpco and is reported in the loss from discontinued operations for the year ended December 31, 2018.