Note 9 - Operating Segment Information - Operating Income (Loss) by Operating Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Drydock expense	$ 1,654	$ 63	$ 4,556	$ 890
General and administrative expenses	8,804	8,854	18,381	18,642
Pre-petition restructuring charges	11,933		17,787
Depreciation and amortization expense	13,578	14,911	27,148	30,950
Impairment charges		46,151		162,808
(Gain) loss on sale of assets and other	(32)	5,914	5,241	5,918
Operating loss	(30,680)	(66,338)	(62,672)	(194,594)
Revenue	24,641	30,487	49,000	69,281
Direct operating expenses	19,384	20,932	38,559	44,667
Total assets	1,071,493		1,071,493		$ 1,053,903
North Sea [Member]
Drydock expense	1,534	36	4,414	873
General and administrative expenses	1,883	1,832	3,672	3,961
Pre-petition restructuring charges	167		167
Depreciation and amortization expense	5,707	6,532	11,325	13,089
Impairment charges				1,986
(Gain) loss on sale of assets and other		5,923		5,923
Operating loss	(4,564)	(5,574)	(10,930)	(7,842)
Revenue	14,939	21,077	28,934	44,009
Direct operating expenses	10,212	12,328	20,286	26,019
Total assets	501,587		501,587		465,908
South East Asia [Member]
Drydock expense	(8)	27	(8)	17
General and administrative expenses	1,015	834	1,775	1,707
Pre-petition restructuring charges	6		6
Depreciation and amortization expense	1,783	2,346	3,565	4,947
Impairment charges		30,268		50,437
(Gain) loss on sale of assets and other	(32)		(32)
Operating loss	(2,847)	(32,388)	(4,465)	(56,491)
Revenue	2,141	4,382	5,309	6,869
Direct operating expenses	2,224	3,295	4,468	6,252
Total assets	152,374		152,374		158,671
Americas [Member]
Drydock expense	128		150
General and administrative expenses	1,428	1,667	3,626	3,698
Pre-petition restructuring charges	45		45
Depreciation and amortization expense	5,488	5,150	11,053	11,118
Impairment charges		15,883		110,385
(Gain) loss on sale of assets and other		(9)	5,273	(5)
Operating loss	(6,476)	(22,972)	(19,195)	(119,189)
Revenue	7,561	5,028	14,757	18,403
Direct operating expenses	6,948	5,309	13,805	12,396
Total assets	407,560		407,560		424,398
Other [Member]
Drydock expense
General and administrative expenses	4,478	4,521	9,308	9,276
Pre-petition restructuring charges	11,715		17,569
Depreciation and amortization expense	600	883	1,205	1,796
Impairment charges
(Gain) loss on sale of assets and other
Operating loss	(16,793)	(5,404)	(28,082)	(11,072)
Revenue
Direct operating expenses
Total assets	$ 9,972		$ 9,972		$ 4,926