Note 9 - Retirement Plans (Details) - Target Asset Allocation	12 Months Ended
	Dec. 31, 2014
Large Cap Equities [Member]
Asset class:
Asset allocations, minimum	23.00%
Asset allocations, maximum	91.00%
Mid Cap Equities [Member]
Asset class:
Asset allocations, minimum	0.00%
Asset allocations, maximum	15.00%
Small Cap Equities [Member]
Asset class:
Asset allocations, minimum	0.00%
Asset allocations, maximum	16.00%
International Equities [Member]
Asset class:
Asset allocations, minimum	5.00%
Asset allocations, maximum	25.00%
Fixed Income Securities [Member]
Asset class:
Asset allocations, minimum	0.00%
Asset allocations, maximum	30.00%
Cash [Member]
Asset class:
Asset allocations, minimum	0.00%
Asset allocations, maximum	20.00%