Note 10 - Change In Accounting Principle - Balance Sheet (Details)	Dec. 31, 2014 USD ($)
Scenario, Previously Reported [Member]
Statement of Financial Position [Abstract]
Prepaid expenses and other current assets	$ 17,318,000
Deferred income taxes	46,688,000
Property and equipment	16,648,000
Accumulated depreciation and amortization	(182,724,000)
Retained earnings	61,082,000
Restatement Adjustment [Member]
Statement of Financial Position [Abstract]
Prepaid expenses and other current assets	(12,121,000)
Deferred income taxes	(3,917,000)
Property and equipment	2,164,000
Accumulated depreciation and amortization	(240,000)
Retained earnings	(6,280,000)
Prepaid expenses and other current assets	5,197,000
Deferred income taxes	42,771,000
Property and equipment	18,812,000
Accumulated depreciation and amortization	(182,964,000)
Retained earnings	$ 54,802,000