Note 8 - Target Asset Allocation (Details)	12 Months Ended
Dec. 31, 2015
Large Cap Value [Member]
Target Range Strategic Allocation	5.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	50.00%
Large Cap Blend [Member]
Target Range Strategic Allocation	5.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	50.00%
Large Cap Growth [Member]
Target Range Strategic Allocation	5.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	50.00%
Mid-cap Blend [Member]
Target Range Strategic Allocation	15.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	40.00%
Small Cap Core [Member]
Target Range Strategic Allocation	5.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	25.00%
Foreign Large Blend [Member]
Target Range Strategic Allocation	10.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	40.00%
Emerging Markets [Member]
Target Range Strategic Allocation	10.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	25.00%
Real Estate [Member]
Target Range Strategic Allocation	5.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	20.00%
US Treasury Securities [Member]
Target Range Strategic Allocation	5.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	25.00%
Intermediate Term Bond [Member]
Target Range Strategic Allocation	10.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	50.00%
US Government Agencies Debt Securities [Member]
Target Range Strategic Allocation	5.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	40.00%
High Yield Bond [Member]
Target Range Strategic Allocation	10.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	25.00%
Emerging Markets Bond [Member]
Target Range Strategic Allocation	10.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	20.00%
Money Market Funds [Member]
Target Range Strategic Allocation	0.00%
Target Range Lower Limit	0.00%
Target Range Upper Limit	100.00%

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

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Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ 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 (d)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

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