Note 8 - Benefit Plans (Details) - Assumptions Used to Determine Benefit Obligations and Net Periodic Benefit	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Corporate Segment [Member]
Note 8 - Benefit Plans (Details) - Assumptions Used to Determine Benefit Obligations and Net Periodic Benefit [Line Items]
Benefit obligations, discount rate	3.86%	4.82%
Benefit obligations, long-term rate of return	8.00%	8.00%
Benefit obligations, salary scale
Net periodic benefit cost, discount rate	4.82%	3.93%
Net periodic benefit cost, long-term rate of return	8.00%	8.00%
Net periodic benefit cost, salary scale		3.00%
Plants [Member]
Note 8 - Benefit Plans (Details) - Assumptions Used to Determine Benefit Obligations and Net Periodic Benefit [Line Items]
Benefit obligations, discount rate	3.74%	4.66%
Benefit obligations, long-term rate of return	8.00%	8.00%
Benefit obligations, salary scale
Net periodic benefit cost, discount rate	4.66%	3.77%
Net periodic benefit cost, long-term rate of return	8.00%	8.00%
Net periodic benefit cost, salary scale

No authoritative reference available.

No definition available.

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- Details

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- Definition

The interest rate used to adjust for the time value of money for the plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(2)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

The interest rate used to adjust for the time value of money.

+ References

+ Details

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(2)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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