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Commitments and Contingencies (Brazilian Customs) - Additional Information (Detail) pure in Millions, R$ in Millions, $ in Millions | 1 Months Ended | 6 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
May 31, 2016 BRL (R$) | Apr. 30, 2011 BRL (R$) | Jun. 30, 2018 USD ($) | Jun. 30, 2018 BRL (R$) | Dec. 31, 2017 USD ($) | Dec. 31, 2017 BRL (R$) | Dec. 31, 2017 BRL (R$)
Commitments and Contingencies Disclosure [Abstract] |  |  |  |  |  |  |
Fines assessed |  | R$ 33.0 | $ 8.5 |  | $ 46.8 |  | R$ 155.0
"Number of Tidewater vessels that the subsidiaries failed to obtain import licenses from | Vessel" |  | 17 |  |  |  |  |
Fines assessed | R$ 3.0 |  | 0.8 |  | 0.9 |  |
Deposit Amount |  |  | 1.5 | R$ 6.0 | 1.8 | R$ 6.0 |
Amount of fines contested |  |  |  |  | 9.1 | 30.0 |
Remaining amount of fine resolved in entity favor |  |  |  |  | $ 36.8 | R$ 122.0 |
Remaining amount of fines contested |  |  | $ 7.7 | R$ 30.0 |  |  |

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- Definition Assessed Fine + References No definition available. + Details
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- Definition Deposit Amount + References No definition available. + Details
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- Definition Number Of Vessels That Subsidiaries Failed To Obtain Import Licenses + References No definition available. + Details
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