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Investment in Unconsolidated Companies - Additional Information (Detail) - USD ($) $ in Thousands		9 Months Ended
		Dec. 31, 2017	Jul. 31, 2017
Schedule of Equity Method Investments [Line Items]
Fresh-start adjustment equity method investment	[1]		$ (24,683)
Fresh-start adjustment, period		10 years
Sonatide Marine, Ltd.
Schedule of Equity Method Investments [Line Items]
Ownership percentage in unconsolidated affiliates		49.00%
Fresh-start adjustment equity method investment		$ 27,700
DTDW Holdings, Ltd.
Schedule of Equity Method Investments [Line Items]
Ownership percentage in unconsolidated affiliates		40.00%
Fresh-start adjustment equity method investment		$ 4,200
Maximum | Sonatide Marine Ltd and DTDW Holdings Ltd.
Schedule of Equity Method Investments [Line Items]
Ownership percentage in unconsolidated affiliates		50.00%
[1] Reflects the adjustment to decrease the carrying value of the company's equity method investments to their estimated fair values which were determined using a discounted cash flow analysis.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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Amount of fresh-start adjustment to investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56426-112766

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6918054&loc=SL2890621-112765

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