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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 + Details
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