Business Acquisitions - Summary of Purchase Price Allocation of Acquired Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020		Jun. 30, 2020
Schedule Of Investments [Line Items]
Equity Investment	$ (71,727)	$ (75,308)
OSV Partners
Schedule Of Investments [Line Items]
Current Assets	6,181
Fixed Assets	35,176
Current Liabilities	(2,186)
Long-Term Liabilities	(15,962)
Total Cost Basis for Purchase	23,209
Purchase Price	(5,331)
Acquisition costs	(598)
Equity Investment	(17,280)	$ (9,094)	[1]
Total Cost Basis for Purchase	$ (23,209)
SEACOR Offshore Delta LLC
Schedule Of Investments [Line Items]
Current Assets				$ 7,700
Fixed Assets				142,282
Current Liabilities				(23,929)
Book Value of Debt Acquired				(100,759)
Discount on Debt Acquired				25,190
Fair Value of Debt Acquired				(75,569)
Total Cost Basis for Purchase				50,484
Purchase Price				(28,150)
Acquisition costs				(112)
Equity Investment				(22,222)
Total Cost Basis for Purchase				$ (50,484)

[1] ^{The Company owned 66.7% of the General Partner and 29.7% of the limited partnership interest of OSV Partners I. On December 31, 2021, the Company purchased the remaining shares in this joint venture that it did not own and consolidated the net assets of OSV Partners. See details below as well as “Note 3. Business Acquisitions”.}