SEGMENT INFORMATION, GEOGRAPHICAL DATA AND MAJOR CUSTOMERS (Tables)

12 Months Ended

Mar. 31, 2017

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, Revenue by Vessel Class

The following table discloses the amount of revenue by segment, and in total for the worldwide fleet, along with the respective percentage of total vessel revenue for the years ended March 31,:

Revenue by vessel class: (In thousands):	2017		% of Vessel Revenue			2016		% of Vessel Revenue			2015		% of Vessel Revenue
Americas fleet:
Deepwater	$	171,334		29	%		235,522		25	%		353,232		24	%
Towing-supply		56,561		10	%		92,768		9	%		125,029		9	%
Other		11,948		2	%		14,705		2	%		27,438		2	%
Total	$	239,843		41	%		342,995		36	%		505,699		35	%
Asia/Pacific fleet:
Deepwater	$	7,252		1	%		60,853		6	%		94,538		6	%
Towing-supply		18,316		3	%		28,192		3	%		53,281		4	%
Other		—		—			—		—			3,001		<1	%
Total	$	25,568		4	%		89,045		9	%		150,820		10	%
Middle East fleet:
Deepwater	$	28,274		5	%		23,596		2	%		28,637		2	%
Towing-supply		60,776		10	%		87,760		10	%		105,642		7	%
Other		—		—			—		—			—		—
Total	$	89,050		15	%		111,356		12	%		134,279		9	%
Africa/Europe fleet:
Deepwater	$	102,374		18	%		205,587		22	%		382,957		26	%
Towing-supply		102,732		18	%		153,818		16	%		219,914		15	%
Other		24,249		4	%		52,599		5	%		74,689		5	%
Total	$	229,355		40	%		412,004		43	%		677,560		46	%
Worldwide fleet:
Deepwater	$	309,234		53	%		525,558		55	%		859,364		58	%
Towing-supply		238,385		41	%		362,538		38	%		503,866		35	%
Other		36,197		6	%		67,304		7	%		105,128		7	%
Total	$	583,816		100	%		955,400		100	%		1,468,358		100	%

Entity Wide Major Customer Amount

The following table discloses our customers that accounted for 10% or more of total revenues during the years ended March 31:

	2017			2016			2015
Chevron Corporation		16.3	%		14.6	%		12.7	%
Freeport McMoRan (A)		11.3	%		3.5	%		1.6	%
Saudi Aramco		10.0	%		7.6	%		5.4	%
Petroleo Brasileiro SA		8.2	%		11.0	%		11.8	%
BP plc		5.8	%		7.1	%		10.1	%