Note 9 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2014

Note 9 - Income Taxes (Tables) [Line Items]

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

(in thousands)	2014			2013			2012
Federal, current	$	(94	)	$	(816	)	$	(707	)
Federal, deferred		12,830			7,560			6,897
State, current		187			102			307
State, deferred		1,851			657			(162	)
	$	14,774		$	7,503		$	6,335

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

(in thousands)	2014			2013			2012
Computed "expected" income tax expense	$	11,404		$	4,462		$	4,340
State income taxes, net of federal income tax effect		1,075			421			409
Per diem allowances		2,304			2,422			2,550
Tax contingency accruals		(104	)		(496	)		(444	)
Valuation allowance (release), net		18			684			(251	)
Tax credits		(112	)		(250	)		(407	)
Other, net		189			260			138
Actual income tax expense	$	14,774		$	7,503		$	6,335

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

(in thousands)	2014			2013
Deferred tax assets:
Insurance and claims	$	16,153		$	11,691
Net operating loss carryovers		18,160			13,681
Other		7,750			6,035
Deferred fuel hedge		8,144			-
Valuation allowance		(1,001	)		(983	)
Total deferred tax assets		49,206			30,424
Deferred tax liabilities:
Property and equipment		(103,186	)		(76,280	)
Other		(2,186	)		(4,793	)
Prepaid expenses		(2,838	)		(3,194	)
Total net deferred tax liabilities		(108,210	)		(84,267	)
Net deferred tax liability	$	(59,004	)	$	(53,843	)

Summary of Valuation Allowance [Table Text Block]

Years ended December 31:	Beginning balance January 1,		Additional provisions to allowance		Write-offs and other deductions			Ending balance December 31,
2014	$	1,736	$	774	$	(743	)	$	1,767
2013	$	1,729	$	457	$	(450	)	$	1,736
2012	$	1,711	$	904	$	(886	)	$	1,729

Summary of Income Tax Contingencies [Table Text Block]

	2014			2013			2012
Balance as of January 1,	$	1,060		$	1,563		$	1,979
Increases related to prior year tax positions		246			-			-
Decreases related to prior year positions		-			-			-
Increases related to current year tax positions		42			24			2
Decreases related to settlements with taxing authorities		(126	)		-			-
Decreases related to lapsing of statute of limitations		(227	)		(527	)		(418	)
Balance as of December 31,	$	995		$	1,060		$	1,563

Valuation Allowance of Deferred Tax Assets [Member]

Note 9 - Income Taxes (Tables) [Line Items]

Summary of Valuation Allowance [Table Text Block]

Years ended December 31:	Beginning balance January 1,		Additional provisions to allowance		Write-offs and other deductions			Ending balance December 31,
2014	$	983	$	401	$	(383	)	$	1,001
2013	$	299	$	684	$	-		$	983