Sale/ Leaseback Arrangements - Additional Information (Detail) $ in Millions	1 Months Ended	3 Months Ended
May 31, 2017 USD ($) Vessel	Jun. 30, 2017 USD ($)
Sale Leaseback Transaction [Line Items]
Lessor claims - sale leaseback agreements		$ 323.6
Deferred gains on sale/leaseback transactions		$ 3.0
Date of petition for bankruptcy		May 17, 2017
Deferred gains credited to reorganization items on account of lease rejections		$ 105.9
Prepackaged Plan
Sale Leaseback Transaction [Line Items]
Number of vessels rejected pursuant to court order \| Vessel	16
Lessor claims - sale leaseback agreements	$ 324.0

Number of vessels rejected in connection with restructuring.

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- Definition

Date petition for bankruptcy filed with the bankruptcy court, in CCYY-MM-DD format.

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- Definition

Amount of gain (loss) on rejection of leases and other executory contracts, reported as a reorganization item.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
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-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56145-112766

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The amount of the provision for expected and allowed claims included in liabilities subject to compromise.

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The portion of the deferred gain that was recognized in the current period.

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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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