Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Current [Abstract]
Federal	$ 0	$ 0	$ 158,000
State	196,000	204,000	247,000
Deferred [Abstract]
Federal	0	(1,249,000)	(5,545,000)
State	7,000	(1,073,000)	(431,000)
Total expense (benefit)	203,000	(2,118,000)	(5,571,000)
Reconciliation of Effective Income Tax Rate [Abstract]
Income tax (benefit) expense at statutory federal rate	(5,199,000)	(13,576,000)	(6,125,000)
Federal income tax effects of: [Abstract]
Non-deductible driver per-diem payments	397,000	438,000	752,000
Non-taxable life insurance transactions	(15,000)	(75,000)	(10,000)
State income taxes and other	(167,000)	(907,000)	(188,000)
Valuation allowance	5,187,000	12,002,000	0
Total expense (benefit)	203,000	(2,118,000)	(5,571,000)
Effective tax rate (in hundredths)	(1.40%)	5.50%	31.80%
Valuation allowance	17,077,000	12,002,000
Deferred Tax Assets [Abstract]
Insurance claims accruals	5,754,000	6,096,000
Allowance for bad debt	631,000	1,016,000
Capital lease obligations	829,000	1,033,000
Deferred compensation	403,000	388,000
Federal and state net operating loss carryforwards	20,623,000	15,399,000
Other	1,273,000	1,350,000
Gross deferred tax assets	29,513,000	25,282,000
Valuation allowance	(17,077,000)	(12,002,000)
Total deferred tax assets	12,436,000	13,280,000
Deferred Tax Liabilities [Abstract]
Capital lease obligations	(780,000)	(1,034,000)
Depreciation	(7,084,000)	(8,687,000)
Prepaid expenses	(4,260,000)	(3,240,000)
Total deferred tax liabilities	(12,124,000)	(12,961,000)
Net deferred tax assets (liabilities)	312,000	319,000
Net deferred tax liabilities	112,000
Tax refunds	496,000	79,000	4,800,000
Taxes paid	231,000	236,000	397,000
Federal gross operating loss carryforwards	49,900,000
Operating loss carryforward expiration date	2028
Windfall tax benefits	$ 111,000