Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Note 14 - Benefit Plans - Weighted-average Asset Allocation (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair values of the Pension Plan's assets	$ 61,870	$ 58,014	$ 46,488
Asset Category, Percentage	100.00%	100.00%
Fixed Income Funds [Member]
Fair values of the Pension Plan's assets	$ 12,257	$ 10,637
Asset Category, Percentage	20.00%	18.00%
Domestic Equity [Member]
Fair values of the Pension Plan's assets	$ 30,731	$ 25,151
Asset Category, Percentage	50.00%	43.00%
International Equity [Member]
Fair values of the Pension Plan's assets	$ 12,380	$ 16,093
Asset Category, Percentage	20.00%	28.00%
Real Estate [Member]
Fair values of the Pension Plan's assets	$ 6,502	$ 6,133
Asset Category, Percentage	10.00%	11.00%
Minimum [Member] \| Fixed Income Funds [Member]
Asset Category, Target	15.00%
Minimum [Member] \| Domestic Equity [Member]
Asset Category, Target	36.50%
Minimum [Member] \| International Equity [Member]
Asset Category, Target	17.00%
Minimum [Member] \| Real Estate [Member]
Asset Category, Target	7.00%
Maximum [Member] \| Fixed Income Funds [Member]
Asset Category, Target	25.00%
Maximum [Member] \| Domestic Equity [Member]
Asset Category, Target	61.50%
Maximum [Member] \| International Equity [Member]
Asset Category, Target	25.00%
Maximum [Member] \| Real Estate [Member]
Asset Category, Target	15.00%