Note 9 - Accrued Retirement Benefits (Details) - Net Periodic Cost (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Pension and other benefits:
Interest cost	$ 3,093us-gaap_DefinedBenefitPlanInterestCost	$ 2,880us-gaap_DefinedBenefitPlanInterestCost
Expected return on plan assets	(3,316)	(2,906)
Recognized net actuarial loss	604	914
Pension expense	381	888
Other changes in plan assets and benefit obligations recognized in comprehensive income:
Net (gain) loss	6,486	(6,973)
Recognized loss	(604)	(914)
Total recognized (gain) loss in comprehensive income	$ 5,882	$ (7,887)

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The amount of gains or losses recognized in net periodic benefit cost.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans, attributable to parent entity.

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Amount after tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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