Consolidated Condensed Statements of Cash Flows (Unaudited) (USD $)	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Net income (loss)	$ 3,611,000	$ (809,000)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Provision for losses on accounts receivable	296,000	358,000
Deferred gain on sales to equity method investee	24,000
Depreciation and amortization	24,387,000	26,768,000
Amortization of deferred financing fees	246,000	197,000
Deferred income tax expense	3,952,000	378,000
Income tax benefit arising from restricted share vesting		(432,000)
Reversal of deferred gain on fuel hedges		(623,000)
Unrealized loss on ineffective portion of fuel hedges	200,000
Casualty premium credit	(4,000,000)
Stock-based compensation expense	534,000	876,000
Equity in income of affiliate	(670,000)	(125,000)
Gain on disposition of property and equipment	(3,842,000)	(4,990,000)
Changes in operating assets and liabilities:
Receivables and advances	(7,328,000)	(4,424,000)
Prepaid expenses and other assets	(158,000)	1,912,000
Inventory and supplies	261,000	(143,000)
Insurance and claims accrual	4,521,000	(1,226,000)
Accounts payable and accrued expenses	4,234,000	(4,956,000)
Net cash flows provided by operating activities	26,268,000	12,761,000
Cash flows from investing activities:
Acquisition of property and equipment	(10,939,000)	(44,969,000)
Investment in affiliated company	(1,000,000)	(1,500,000)
Return of investment in affiliated company	139,000
Proceeds from disposition of property and equipment	37,685,000	32,829,000
Net cash flows provided by /(used in) investing activities	25,885,000	(13,640,000)
Cash flows from financing activities:
Change in checks outstanding in excess of bank balances	2,078,000	2,531,000
Proceeds from issuance of notes payable	250,000	23,657,000
Income tax benefit arising from restricted share vesting		432,000
Repayments of notes payable	(43,142,000)	(45,581,000)
Repayments of capital lease obligations	(962,000)	(728,000)
(Repayments)/proceeds under revolving credit facility, net	(9,859,000)	14,036,000
Payment of minimum tax withholdings on stock compensation		(540,000)
Debt refinancing costs	(27,000)	(8,000)
Net cash used in financing activities	(51,662,000)	(6,201,000)
Net change in cash and cash equivalents	491,000	(7,080,000)
Cash and cash equivalents at beginning of period	3,895,000	9,361,000
Cash and cash equivalents at end of period	$ 4,386,000	$ 2,281,000