Business Combinations and Goodwill - Changes In Carrying Amount Of Goodwill (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)
Goodwill [Line Items]
Impairment loss	$ (6,689)
Well Intervention
Goodwill [Line Items]
Balance at beginning of year	7,157
Impairment loss	(6,689)
Foreign currency adjustments	$ (468)

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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