Investment in Unconsolidated Companies (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Mar. 31, 2016
Sonatide Marine, Ltd.
Schedule of Equity Method Investments [Line Items]
Ownership percentage in unconsolidated affiliates	49.00%
Investments in, at equity, and advances to unconsolidated companies	$ 45,115	$ 37,141
DTDW Holdings, Ltd.
Schedule of Equity Method Investments [Line Items]
Ownership percentage in unconsolidated affiliates	40.00%
Investments in, at equity, and advances to unconsolidated companies		361
Sonatide Marine Ltd and DTDW Holdings Ltd.
Schedule of Equity Method Investments [Line Items]
Investments in, at equity, and advances to unconsolidated companies	$ 45,115	$ 37,502

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

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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This item represents the entity's ownership percentage in the investee multiplied by the investee's total equity.

+ 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)(3)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

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+ References

No definition available.

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