Goodwill and Other Intangibles - Schedule of Acquired Intangibles (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2018 USD ($)
Acquired Finite Lived Intangible Assets [Line Items]
Acquired intangibles subject to amortization and not subject to amortization	$ 21,720
Water Rights
Acquired Finite Lived Intangible Assets [Line Items]
Acquired intangibles not subject to amortization	1,100
Customer Relationships
Acquired Finite Lived Intangible Assets [Line Items]
Acquired intangibles subject to amortization	$ 20,620
Acquired Finite-lived Intangible Assets, Useful Life	12 years

Finite-lived and indefinite-lived intangible assets acquired.

No definition available.

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Data Type:	xbrli:monetaryItemType
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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.

+ Details

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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- Definition

Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, from an acquisition.

+ References

No definition available.

+ Details

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- Details

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