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Asset Impairments - Additional Information (Detail) | 1 Months Ended | 3 Months Ended | 4 Months Ended | 5 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jul. 31, 2017 USD ($) | Dec. 31, 2017 USD ($) | Jun. 30, 2017 USD ($) | Mar. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Sep. 30, 2016 USD ($) | Jun. 30, 2016 USD ($) | Jul. 31, 2017 USD ($) Vessel | Dec. 31, 2017 USD ($) Vessel | Mar. 31, 2017 USD ($) Vessel
Derivatives, Fair Value [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Asset impairments |  | $ 16,777,000 |  |  |  |  |  |  |  | $ 16,777,000 | [1] |  |
Number of vessels impaired during the period | Vessel |  |  |  |  |  |  |  |  |  | 5 |  |  |
Fair value of assets incurring impairment |  |  |  |  |  |  |  |  |  | $ 8,763,000 |  |  |
Stacked Vessels |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Asset impairments |  |  |  |  |  |  |  |  |  | $ 14,400,000 |  |  |
Number of vessels impaired during the period | Vessel |  |  |  |  |  |  |  |  |  | 5 |  |  |
Fair value of assets incurring impairment |  |  |  |  |  |  |  |  |  | $ 8,800,000 |  |  |
Active Vessels |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Asset impairments |  |  |  |  |  |  |  |  |  | $ 0 |  |  |
Predecessor |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Asset impairments | $ 21,325,000 |  | $ 163,423,000 | $ 64,857,000 | $ 253,422,000 | $ 129,562,000 | $ 36,886,000 | $ 184,748,000 | [1] |  |  | $ 484,727,000 | [1]
Number of vessels impaired during the period | Vessel |  |  |  |  |  |  |  | 79 |  |  |  | 132 |
Fair value of assets incurring impairment |  |  |  |  |  |  |  | $ 571,821,000 |  |  |  | $ 933,068,000 |
Predecessor | Stacked Vessels |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Asset impairments |  |  |  |  |  |  |  | $ 157,800,000 |  |  |  |  |
Number of vessels impaired during the period | Vessel |  |  |  |  |  |  |  | 73 |  |  |  |  |
Fair value of assets incurring impairment |  |  |  |  |  |  |  | $ 505,600,000 |  |  |  |  |
Predecessor | Active Vessels |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Asset impairments |  |  |  |  |  |  |  | $ 26,900,000 |  |  |  |  |
Number of vessels impaired during the period | Vessel |  |  |  |  |  |  |  | 6 |  |  |  |  |
Fair value of assets incurring impairment |  |  |  |  |  |  |  | $ 66,200,000 |  |  |  |  |
[1] | The period August 1, 2017 through December 31, 2017 and the year ended March 31, 2017 included $2.3 million and $2.2 million, respectively, of impairments related to inventory and other non-vessel assets.

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