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- Definition

Debt Instrument Aggregate Rate

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- Definition

Debt Instrument, Maturity, Month and Year

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- Definition

Debt instrument sub-tranche premium rate.

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- Definition

Modification description of debt instrument.

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No definition available.

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- Definition

Number of vessels mortgaged.

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Percentage of required principal payments due from effective date.

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No definition available.

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Prepackaged plan effective date.

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No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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Indebtedness - Senior Debt Notes - Additional Information (Detail) kr in Thousands, $ in Thousands		1 Months Ended
	Jul. 31, 2017 Vessel	May 27, 2015 USD ($)	Mar. 31, 2015 USD ($)	Jan. 31, 2014 NOK (kr)	May 31, 2012 NOK (kr)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 NOK (kr)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 NOK (kr)
Debt [Line Items]
Debt instrument outstanding amount						$ 431,456		$ 438,827
Notes Due May 2024
Debt [Line Items]
Debt instrument maturity, month and year					2024-05
Aggregate principal amount \| kr					kr 204,400
Indebtedness rate				1.25%
Indebtedness sub-tranche premium rate				1.00%
Total capitalization rate				6.13%
Debt instrument outstanding amount						12,200	kr 106,500
Debt instrument fixed interest rate					3.88%
Troms Offshore Supply AS \| Notes Due April 2027
Debt [Line Items]
Debt instrument maturity, month and year		2027-04
Aggregate principal amount		$ 31,300
Debt instrument bearing floating interest rate		2.92%
Indebtedness rate		1.00%
Indebtedness sub-tranche premium rate		1.00%
Total capitalization rate		4.92%
Debt instrument outstanding amount						24,200
Troms Offshore Supply AS \| Notes Due January 2027
Debt [Line Items]
Debt instrument maturity, month and year			2027-01
Aggregate principal amount			$ 29,500
Debt instrument bearing floating interest rate			2.91%
Indebtedness rate			1.00%
Indebtedness sub-tranche premium rate			1.00%
Total capitalization rate			4.91%
Debt instrument outstanding amount						22,100
Troms Offshore Supply AS \| Notes Due January 2026
Debt [Line Items]
Debt instrument maturity, month and year				2026-01
Aggregate principal amount \| kr				kr 300,000
Indebtedness rate				1.25%
Indebtedness sub-tranche premium rate				1.00%
Total capitalization rate				4.56%
Debt instrument outstanding amount						22,988	200,000	25,965	kr 212,500
Troms Offshore Supply AS \| Notes Due January 2026 \| Minimum
Debt [Line Items]
Debt instrument bearing floating interest rate				2.31%
Troms Offshore Supply AS \| Notes Due May 2024
Debt [Line Items]
Debt instrument outstanding amount						$ 12,241	kr 106,500	$ 14,054	kr 115,020
Troms Offshore Supply AS \| Plan of Reorganization \| Senior Notes
Debt [Line Items]
Plan effective date	Jul. 31, 2017
Modification description of debt instrument	(i) reduce by 50% the required principal payments due from the Effective Date through March 31, 2019, (ii) modestly increase the interest rates on amounts outstanding through April 2023, and (iii) provide for security and additional guarantees, including (a) mortgages on six vessels and related assignments of earnings and insurances, (b) share pledges by Troms Offshore and certain subsidiaries of Troms Offshore, and (c) guarantees by certain subsidiaries of Troms Offshore.
Percentage of required principal payments due from effective date	50.00%
Number of vessels mortgaged \| Vessel	6