Note 7 - Pensions and Other Postretirement Benefits (Details) - Expected Future Benefit Payments (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Pension Plan [Member]
Note 7 - Pensions and Other Postretirement Benefits (Details) - Expected Future Benefit Payments [Line Items]
Defined Benefit Plan Expected Future Benefit Payments, Year One	$ 5,095
Defined Benefit Plan Expected Future Benefit Payments, Year Two	5,319
Defined Benefit Plan Expected Future Benefit Payments, Year Three	7,044
Defined Benefit Plan Expected Future Benefit Payments, Year Four	6,089
Defined Benefit Plan Expected Future Benefit Payments, Year Five	6,366
Defined Benefit Plan Expected Future Benefit Payments, Thereafter	30,780
Postretirement Benefits [Member]
Note 7 - Pensions and Other Postretirement Benefits (Details) - Expected Future Benefit Payments [Line Items]
Defined Benefit Plan Expected Future Benefit Payments, Year One	1,543
Defined Benefit Plan Expected Future Benefit Payments, Year Two	1,576
Defined Benefit Plan Expected Future Benefit Payments, Year Three	1,612
Defined Benefit Plan Expected Future Benefit Payments, Year Four	1,695
Defined Benefit Plan Expected Future Benefit Payments, Year Five	1,781
Defined Benefit Plan Expected Future Benefit Payments, Thereafter	$ 8,957

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Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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 (f)

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

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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