Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Property, Plant and Equipment [Line Items]
Depreciation expenses	$ 15,562	$ 13,233
Water Treatment Facilities [Member]
Property, Plant and Equipment [Line Items]
Business acquisition, assets acquired and liabilities assumed, net	4,172
Business acquisition, other current liabilities	553
Business acquisition, other non-current liabilities	3,619
Proceeds from sale leaseback facility	$ 4,172
Sale leaseback facility, term	10 years

Sale Leaseback Contractual Lease Term

No definition available.

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- Definition

Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

+ References

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

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- Definition

Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

+ References

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of cash inflow after closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in financing activities.

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