Segment Information - Schedule of Segment Reporting Information, by Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023		Mar. 31, 2022		Dec. 31, 2022
Segment Reporting Information [Line Items]
Operating Revenues	$ 59,973		$ 45,591
Direct Costs and Expenses	37,273		39,496
Direct Vessel Profit (Loss)	22,700		6,095
Lease expense	720		1,060
Administrative and general	11,632		9,924
Depreciation and amortization	13,762		14,371
Other Costs and Expenses	26,114		25,355
Gains on asset dispositions and impairments, net	3,599		2,139
Operating Loss	185		(17,121)
Historical cost	969,328		1,006,873		$ 967,683
Accumulated depreciation	(324,197)		(316,444)		(310,778)
Property and equipment	645,131		690,429		$ 656,905
Total Assets	749,144	[1]	818,255	[2]
Time Charter
Segment Reporting Information [Line Items]
Operating Revenues	55,415		42,741
Bareboat Charter
Segment Reporting Information [Line Items]
Operating Revenues	360		618
Other Marine Services
Segment Reporting Information [Line Items]
Operating Revenues	4,198		2,232
Personnel
Segment Reporting Information [Line Items]
Direct Costs and Expenses	19,803		18,435
Repairs and Maintenance
Segment Reporting Information [Line Items]
Direct Costs and Expenses	6,011		6,791
Drydocking
Segment Reporting Information [Line Items]
Direct Costs and Expenses	13		4,973
Insurance and Loss Reserves
Segment Reporting Information [Line Items]
Direct Costs and Expenses	2,789		1,186
Fuel, Lubes and Supplies
Segment Reporting Information [Line Items]
Direct Costs and Expenses	4,819		3,729
Other Direct Costs and Expenses
Segment Reporting Information [Line Items]
Direct Costs and Expenses	3,838		4,382
UNITED STATES
Segment Reporting Information [Line Items]
Operating Revenues	10,406		9,916
Direct Costs and Expenses	9,819		10,006
Direct Vessel Profit (Loss)	587		(90)
Lease expense	136		287
Depreciation and amortization	3,535		4,638
Historical cost	208,241		280,472
Accumulated depreciation	(99,165)		(130,455)
Property and equipment	109,076		150,017
Total Assets	146,209	[1]	173,269	[2]
UNITED STATES | Time Charter
Segment Reporting Information [Line Items]
Operating Revenues	6,564		7,864
UNITED STATES | Bareboat Charter
Segment Reporting Information [Line Items]
Operating Revenues	0		0
UNITED STATES | Other Marine Services
Segment Reporting Information [Line Items]
Operating Revenues	3,842		2,052
UNITED STATES | Personnel
Segment Reporting Information [Line Items]
Direct Costs and Expenses	6,535		4,923
UNITED STATES | Repairs and Maintenance
Segment Reporting Information [Line Items]
Direct Costs and Expenses	1,194		1,101
UNITED STATES | Drydocking
Segment Reporting Information [Line Items]
Direct Costs and Expenses	43		2,867
UNITED STATES | Insurance and Loss Reserves
Segment Reporting Information [Line Items]
Direct Costs and Expenses	1,041		229
UNITED STATES | Fuel, Lubes and Supplies
Segment Reporting Information [Line Items]
Direct Costs and Expenses	783		662
UNITED STATES | Other Direct Costs and Expenses
Segment Reporting Information [Line Items]
Direct Costs and Expenses	223		224
Africa and Europe, Continuing Operations
Segment Reporting Information [Line Items]
Operating Revenues	18,162		11,664
Direct Costs and Expenses	12,465		9,684
Direct Vessel Profit (Loss)	5,697		1,980
Lease expense	429		402
Depreciation and amortization	3,925		3,258
Historical cost	287,168		241,607
Accumulated depreciation	(96,086)		(77,502)
Property and equipment	191,082		164,105
Total Assets	216,899	[1]	181,526	[2]
Africa and Europe, Continuing Operations | Time Charter
Segment Reporting Information [Line Items]
Operating Revenues	18,996		12,280
Africa and Europe, Continuing Operations | Bareboat Charter
Segment Reporting Information [Line Items]
Operating Revenues	0		0
Africa and Europe, Continuing Operations | Other Marine Services
Segment Reporting Information [Line Items]
Operating Revenues	(834)		(616)
Africa and Europe, Continuing Operations | Personnel
Segment Reporting Information [Line Items]
Direct Costs and Expenses	4,505		3,536
Africa and Europe, Continuing Operations | Repairs and Maintenance
Segment Reporting Information [Line Items]
Direct Costs and Expenses	2,553		1,579
Africa and Europe, Continuing Operations | Drydocking
Segment Reporting Information [Line Items]
Direct Costs and Expenses	1,184		1,144
Africa and Europe, Continuing Operations | Insurance and Loss Reserves
Segment Reporting Information [Line Items]
Direct Costs and Expenses	318		124
Africa and Europe, Continuing Operations | Fuel, Lubes and Supplies
Segment Reporting Information [Line Items]
Direct Costs and Expenses	2,215		1,473
Africa and Europe, Continuing Operations | Other Direct Costs and Expenses
Segment Reporting Information [Line Items]
Direct Costs and Expenses	1,690		1,828
Middle East and Asia
Segment Reporting Information [Line Items]
Operating Revenues	15,886		13,709
Direct Costs and Expenses	8,077		11,969
Direct Vessel Profit (Loss)	7,809		1,740
Lease expense	76		31
Depreciation and amortization	3,688		4,345
Historical cost	286,795		335,121
Accumulated depreciation	(93,132)		(86,682)
Property and equipment	193,663		248,439
Total Assets	213,461	[1]	254,749	[2]
Middle East and Asia | Time Charter
Segment Reporting Information [Line Items]
Operating Revenues	16,028		13,660
Middle East and Asia | Bareboat Charter
Segment Reporting Information [Line Items]
Operating Revenues	0		0
Middle East and Asia | Other Marine Services
Segment Reporting Information [Line Items]
Operating Revenues	(142)		49
Middle East and Asia | Personnel
Segment Reporting Information [Line Items]
Direct Costs and Expenses	4,841		6,031
Middle East and Asia | Repairs and Maintenance
Segment Reporting Information [Line Items]
Direct Costs and Expenses	677		1,832
Middle East and Asia | Drydocking
Segment Reporting Information [Line Items]
Direct Costs and Expenses	(1,095)		962
Middle East and Asia | Insurance and Loss Reserves
Segment Reporting Information [Line Items]
Direct Costs and Expenses	1,185		507
Middle East and Asia | Fuel, Lubes and Supplies
Segment Reporting Information [Line Items]
Direct Costs and Expenses	1,142		1,010
Middle East and Asia | Other Direct Costs and Expenses
Segment Reporting Information [Line Items]
Direct Costs and Expenses	1,327		1,627
Latin America
Segment Reporting Information [Line Items]
Operating Revenues	15,519		10,302
Direct Costs and Expenses	6,912		7,837
Direct Vessel Profit (Loss)	8,607		2,465
Lease expense	79		340
Depreciation and amortization	2,614		2,130
Historical cost	187,124		149,673
Accumulated depreciation	(35,814)		(21,805)
Property and equipment	151,310		127,868
Total Assets	172,575	[1]	208,711	[2]
Latin America | Time Charter
Segment Reporting Information [Line Items]
Operating Revenues	13,827		8,937
Latin America | Bareboat Charter
Segment Reporting Information [Line Items]
Operating Revenues	360		618
Latin America | Other Marine Services
Segment Reporting Information [Line Items]
Operating Revenues	1,332		747
Latin America | Personnel
Segment Reporting Information [Line Items]
Direct Costs and Expenses	3,922		3,945
Latin America | Repairs and Maintenance
Segment Reporting Information [Line Items]
Direct Costs and Expenses	1,587		2,279
Latin America | Drydocking
Segment Reporting Information [Line Items]
Direct Costs and Expenses	(119)		0
Latin America | Insurance and Loss Reserves
Segment Reporting Information [Line Items]
Direct Costs and Expenses	245		326
Latin America | Fuel, Lubes and Supplies
Segment Reporting Information [Line Items]
Direct Costs and Expenses	679		584
Latin America | Other Direct Costs and Expenses
Segment Reporting Information [Line Items]
Direct Costs and Expenses	$ 598		$ 703

[1] Total assets by region does not include corporate assets of $54.4 million as of March 31, 2023.

[2] Total assets by region does not include corporate assets of $84.4 million as of March 31, 2022.