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Summary of Debt Outstanding Based On Stated Maturities (Parenthetical) (Detail) | 12 Months Ended
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Dec. 31, 2018
8.00% Secured Notes Due August 2022 |
Debt [Line Items] |
Debt instrument interest rate | 8.00%
Debt Instrument Maturity Period | August 2022
Norwegian Kroner Denominated Notes Due May 2024 | Troms Offshore Supply AS |
Debt [Line Items] |
Debt Instrument Maturity Period | May 2024
Norwegian Kroner Denominated Notes Due January 2026 | Troms Offshore Supply AS |
Debt [Line Items] |
Debt Instrument Maturity Period | January 2026
United States Dollar Denominated Notes Due January 2027 | Troms Offshore Supply AS |
Debt [Line Items] |
Debt Instrument Maturity Period | January 2027
United States Dollar Denominated Notes Due April 2027 | Troms Offshore Supply AS |
Debt [Line Items] |
Debt Instrument Maturity Period | April 2027

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + 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)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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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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