Contingencies And Commitments [Line Items]

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- Definition

Number Of Charges

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No definition available.

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- Definition

Number Of Installments

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- Definition

Probationary Period

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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-Publisher FASB
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- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

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- Definition

Amount of loss contingency liability.

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- Definition

Amount of damages paid to the plaintiff in the legal matter.

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-Name Accounting Standards Codification
-Topic 450
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- Definition

The estimated maximum amount of possible loss from the contingency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 450
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Commitments and Contingencies - Additional Information (Detail)	Apr. 08, 2016 USD ($)	Jul. 20, 2015 USD ($)	Oct. 01, 2014 USD ($) Charge	Apr. 21, 2017 USD ($)	Aug. 25, 2014 USD ($) Installment
Contingencies And Commitments [Line Items]
Number of misdemeanor charges to which the company pleaded guilty \| Charge			3
Fine for violation of Clean Water Act			$ 600,000
Period of probation			2 years
Civil penalties per violation					$ 3,000,000
Number of installments for payment of civil penalty \| Installment					2
Estimated site restoration costs					$ 13,000,000
First Installment [Member]
Contingencies And Commitments [Line Items]
Civil penalty payment plus interest		$ 1,000,000
Second Installment [Member] \| Subsequent Event [Member]
Contingencies And Commitments [Line Items]
Civil penalty payment plus interest	$ 250,000
Third Installment [Member] \| Scenario, Forecast [Member]
Contingencies And Commitments [Line Items]
Civil penalty payment due plus interest				$ 1,750,000