Discontinued Operations - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended
Jan. 12, 2021	Mar. 31, 2021	Mar. 31, 2020
Windcat Workboats Holdings Ltd \| Discontinued Operations, Held-for-sale
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net income from operations	$ 200	$ 169	$ (2,054)

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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