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Goodwill - Changes In Carrying Amount Of Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Goodwill [Line Items]
Balance at beginning of year			$ 7,157
Impairment loss	$ 0	$ 0	(6,689)	$ 0
Balance at end of period	0		0
Well Intervention
Goodwill [Line Items]
Balance at beginning of year			7,157
Impairment loss			(6,689)
Other adjustments			(468)
Balance at end of period	$ 0		$ 0