Note 13 - Income Taxes (Details) - Deferred Income Taxes (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets:
Inventory (excluding LIFO reserve)	$ 2,881us-gaap_DeferredTaxAssetsInventory	$ 2,588us-gaap_DeferredTaxAssetsInventory
Net operating loss and tax credit carryforwards	2,971	3,044
Allowance for doubtful accounts	519	585
Accrued expenses	7,642	7,459
Other	83us-gaap_DeferredTaxAssetsOther	83us-gaap_DeferredTaxAssetsOther
	14,096us-gaap_DeferredTaxAssetsGross	13,759us-gaap_DeferredTaxAssetsGross
Valuation reserve	(1,381)	(1,298)
Total deferred tax assets	12,715us-gaap_DeferredTaxAssetsNet	12,461us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities:
LIFO reserve	(6,049)	(6,213)
Property and equipment	(22,684)	(24,339)
Intangibles	(14,930)	(15,259)
Other	24us-gaap_DeferredTaxLiabilitiesOther	(24)us-gaap_DeferredTaxLiabilitiesOther
Total deferred tax liabilities	(43,639)us-gaap_DeferredIncomeTaxLiabilities	(45,835)us-gaap_DeferredIncomeTaxLiabilities
Deferred tax liabilities, net	$ (30,924)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ (33,374)us-gaap_DeferredTaxAssetsLiabilitiesNet

Amount of deferred tax liability attributable to taxable temporary differences.

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