Note 8 - Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Note 8 - Income Taxes (Details) [Line Items]
Deferred Tax Assets, Valuation Allowance		$ 2,748,000	$ 3,157,000
Increase (Decrease) in Pension Plan Obligations		16,000,000	6,200,000	13,800,000
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax		9,761,000	(3,768,000)	(8,414,000)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Tax		6,200,000	2,400,000	5,400,000
Income Taxes Paid, Net		500,000	800,000	500,000
Accrued Income Taxes		1,500,000	1,900,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate		1,500,000	1,600,000
Liability for Uncertain Tax Positions, Current		700,000	700,000
Unrecognized Tax Benefits, Period Increase (Decrease)	(100,000)
Domestic Tax Authority [Member]
Note 8 - Income Taxes (Details) [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration		225,100,000
State and Local Jurisdiction [Member] | Valuation Allowance, Operating Loss Carryforwards [Member]
Note 8 - Income Taxes (Details) [Line Items]
Deferred Tax Assets, Valuation Allowance		2,700,000	3,200,000
State and Local Jurisdiction [Member]
Note 8 - Income Taxes (Details) [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration		245,000,000
Capital Loss Carryforward [Member]
Note 8 - Income Taxes (Details) [Line Items]
Valuation Allowance, Deferred Tax Asset, Change in Amount		$ 400,000	$ 1,500,000