Note 13 - Reserves (Details) - Allowance for Doubtful Accounts and Reserves for Environmental Liabilities (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Allowance for Doubtful Accounts [Member]
Allowance for Doubtful Accounts
Beginning of year	$ 163,000	$ 262,000
Increase	31,000	92,000
Decrease		(191,000)
End of year	194,000	163,000
Reserve for Environmental Costs [Member]
Allowance for Doubtful Accounts
Beginning of year	165,000	675,000
Increase		41,000
Decrease	(23,000)	(551,000)
End of year	$ 142,000	$ 165,000

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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- Definition

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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