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Summary of Norwegian Kroner (NOK) Denominated Borrowings Outstanding (Parenthetical) (Detail) - Troms Offshore Supply AS | 9 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Mar. 31, 2017
January 2014 notes |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | January 2014 |
January 2014 notes | Predecessor |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period |  | January 2014
May 2012 notes |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | May 2012 |
May 2012 notes | Predecessor |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period |  | May 2012

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- Definition Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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