Amount spent to complete work specified in work plans for source control work.

No definition available.

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- Definition

The estimated cost of the remedy selected by EPA.

+ References

No definition available.

+ Details

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- Definition

The estimated amount of time to complete the selected EPA remedy.

+ References

No definition available.

+ Details

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- Definition

Number of potentially responsible parties for Portland Harbor Superfund site.

+ References

No definition available.

+ Details

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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
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

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Balance Type:	credit
Period Type:	instant

- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of payments made reducing loss contingency liability.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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- Details

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Note 13 - Commitments and Contingencies (Details Textual) $ in Millions	1 Months Ended		12 Months Ended
	Jan. 31, 2015 USD ($)	Jul. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2013 USD ($)
Portland Harbor Natural Resources Trustee Council [Member]
Loss Contingency Accrual, Payments	$ 0.2	$ 0.2
Loss Contingency, Accrual, Current					$ 0.4
Voluntary Cleanup Program [Member] \| Minimum [Member]
Loss Contingency, Estimate of Possible Loss			$ 0.2
Voluntary Cleanup Program [Member] \| Maximum [Member]
Loss Contingency, Estimate of Possible Loss			2.2
Voluntary Cleanup Program [Member] \| Estimated [Member]
Accrual for Environmental Loss Contingencies			0.3
Minimum [Member]
Estimated Cost of Epa Selected Remedy			790.0
Maximum [Member]
Estimated Cost of Epa Selected Remedy			$ 2,500.0
Estimated Time to Complete Selected Epa Remedy			18 years
Amount Spent To Complete Work Specified In Work Plans			$ 0.2	$ 0.1		$ 0.1
Number Of Potentially Responsible Parties			100
Insurance Recoveries	$ 2.6
Letters of Credit Outstanding, Amount			$ 2.1