Environmental Settlement and Related Costs - Additional Information (Detail)	Oct. 01, 2014 USD ($) Charge	Aug. 25, 2014 USD ($)
Environmental Remediation Obligations [Abstract]
Fines associated with the Consent Decree amount		$ 3,000,000
Preliminarily estimated cost of restoration		3,000,000
Maximum cost of restoration		$ 9,000,000
Fine agreed to pay for violation of the Clean Water Act	$ 600,000
Period of probation	2 years
Number of misdemeanor charges to which the company pleaded guilty \| Charge	3

Fines for failure to comply with environmental protection requirements.

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Number Of Charges

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Probationary Period

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Estimate of reasonably possible loss exposure in excess of amount accrued for remediation, site restoration, postclosure, monitoring commitments, or other exit costs associated with the sale, disposal or abandonment of a particular property resulting from unanticipated contamination of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Number Topic 5

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High-end estimate of the reasonably possible loss exposure in excess of the amount accrued for remediation, site restoration, postclosure, monitoring commitments, or other exit costs associated with the sale, disposal or abandonment of a particular property resulting from unanticipated contamination of the assets.

+ References

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-Subparagraph (SAB TOPIC 5.Y.Q4)

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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

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