Note 5 - Income Taxes (Details) - Net Deferred Tax Liability (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Net Deferred Tax Liability [Abstract]
Reserves and accrued liabilities	$ 6,051	$ 5,687
Other	2,796	2,714
	8,847	8,401
Depreciation	116,438	111,794
Prepaid expenses	2,631	2,526
	119,069	114,320
Net deferred tax liability	$ 110,222	$ 105,919