Commitments and Contingencies - Additional Information (Detail) $ in Millions	Sep. 29, 2017 USD ($)
LNG Vessel Charter
Other Commitments [Line Items]
Expected commitment	$ 5.0

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.

No definition available.

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Balance Type:	na
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