Amount anticipated to spent for further source control work during the upcoming fiscal year.

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- Definition

Estimated cost of EPA selected remedy.

+ References

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Estimated time to complete selected EPA remedy.

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- Definition

Number of potentially responsible parties for Portland Harbor Superfund site.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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

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Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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Amount of payments made reducing loss contingency liability.

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Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

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Commitments and Contingencies - Additional Information (Detail) (USD $)	1 Months Ended		1 Months Ended	9 Months Ended		9 Months Ended
	Jun. 30, 2007	Sep. 30, 2014 Parties	Jul. 31, 2014 Portland Harbor Natural Resources Trustee Council [Member]	Sep. 30, 2014 Portland Harbor Natural Resources Trustee Council [Member]	Jun. 30, 2014 Portland Harbor Natural Resources Trustee Council [Member]	Sep. 30, 2014 Minimum [Member]	Sep. 30, 2014 Maximum [Member]
Other Commitments [Line Items]
Company made payment to Lower Willamette Group as interim settlement	$ 175,000
Estimated cost						169,000,000	1,760,000,000
Estimated years to implement						2 years	28 years
Amount anticipated to spent for further Source Control work		100,000
Injury assessment process, payment			216,000
Injury assessment process, yet to paid				144,000
Injury assessment process, outstanding					360,000
Number of potentially responsible parties		100
Total stand-by letters of credit		$ 3,100,000