Commitments and Contingencies - Legal Proceedings - Additional Information (Detail)	3 Months Ended
Mar. 31, 2016 Plaintiff
Calcasieu River Estuary in Lake Charles Louisiana [Member]
Loss Contingencies [Line Items]
Number of individuals that have filed lawsuits against the Company	2,607

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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