Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
OPERATING ACTIVITIES:
Net income	$ 6,302	$ 2,226
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	18,292	19,860
Bad debt expense	376	420
Sale leaseback deferred gain amortization	(93)
Stock compensation-net of excess tax benefits	115	276
Provision for deferred income taxes	3,442	1,406
Reclassification of unrealized loss on marketable equity securities	1	27
Recognized gain on marketable equity securities	(49)	(27)
Gain on sale or disposal of equipment	(2,787)	(355)
Changes in operating assets and liabilities:
Accounts receivable	(4,368)	(11,263)
Prepaid expenses, deposits, inventories, and other assets	(30)	4,094
Income taxes payable	208	(10)
Trade accounts payable	3,040	3,548
Accrued expenses and other liabilities	2,423	3,823
Net cash provided by operating activities	26,872	24,025
INVESTING ACTIVITIES:
Purchases of property and equipment	(19,061)	(40,545)
Proceeds from disposition of equipment	24,271	13,879
Change in restricted cash	(764)	(2,973)
Sales of marketable equity securities		13
Purchases of marketable equity securities, net of return of capital	19	11
Net cash provided by (used in) investing activities	4,465	(29,615)
FINANCING ACTIVITIES:
Borrowings under line of credit	257,919	209,926
Repayments under line of credit	(252,401)	(206,986)
Borrowings of long-term debt	17,048	22,177
Repayments of long-term debt	(40,242)	(19,171)
Borrowings under margin account	45	78
Repayments under margin account	(442)	(406)
Repurchases of common stock	(14,808)	(470)
Exercise of stock options	463
Net cash (used in) provided by financing activities	(32,418)	5,148
NET DECREASE IN CASH AND CASH EQUIVALENTS	(1,081)	(442)
CASH AND CASH EQUIVALENTS-Beginning of period	1,172	507
CASH AND CASH EQUIVALENTS-End of period	91	65
Cash paid during the period for:
Interest	1,640	1,722
Income taxes	408	46
NONCASH INVESTING AND FINANCING ACTIVITIES-
Purchases of property and equipment included in accounts payable	$ 31	$ 10,966