Note 7 - Pensions and Other Postretirement Benefits (Details) - Components of Net Periodic Benefit Cost (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pension Plan [Member]
Note 7 - Pensions and Other Postretirement Benefits (Details) - Components of Net Periodic Benefit Cost [Line Items]
Service cost	$ 2,904	$ 3,144	$ 3,188
Interest cost	2,896	2,851	2,803
Expected return on plan assets	(4,755)	(5,080)	(4,591)
Recognized actuarial loss (gain)	(7,219)	5,328	2,441
Settlement loss		4,169	2,935
Net periodic benefit cost	2,708	7,164	6,776
Other changes in pension plan assets and benefit obligations recognized in other comprehensive loss:
Net loss (gain)	4,541	(10,734)	1,371
Total expense (income) recognized in net periodic benefit cost and other comprehensive income	7,249	(3,570)	8,147
Postretirement Benefits [Member]
Note 7 - Pensions and Other Postretirement Benefits (Details) - Components of Net Periodic Benefit Cost [Line Items]
Service cost	907	1,153	1,156
Interest cost	845	724	871
Recognized actuarial loss (gain)	(3,052)	4,439	(647)
Net periodic benefit cost	571	1,154	1,380
Other changes in pension plan assets and benefit obligations recognized in other comprehensive loss:
Net loss (gain)	4,233	(3,717)	(384)
Total expense (income) recognized in net periodic benefit cost and other comprehensive income	$ 4,804	$ (2,563)	$ 996

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Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

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The amount of decrease that is related to an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

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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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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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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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