CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Cash flows from operating activities:
Net income	$ 4,675	$ 11,296
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	8,955	8,195
Amortization of discount and deferred debt issuance costs	870	870
Share-based compensation	469	704
Deferred income taxes, net	(2,944)	1,964
Provision for losses on accounts receivable	2,604	1,818
Loss on sale of assets	38	102
Changes in operating assets and liabilities	(3,073)	(15,779)
Cash provided by operating activities	11,594	9,170
Cash flows from investing activities:
Purchases of property and equipment	(4,563)	(4,103)
Acquisitions of businesses, net of cash acquired	(543)	(7)
Proceeds from sale of assets	103	81
Cash used in investing activities	(5,003)	(4,029)
Cash flows from financing activities:
Long-term debt repayments	(2,205)	(6,904)
Payments on obligations under capital lease	(1,832)	(1,594)
Debt issuance costs		(8)
Cash used in financing activities	(4,037)	(8,506)
Effect of exchange rate changes on cash and cash equivalents	(88)	(66)
Increase (decrease) in cash and cash equivalents	2,466	(3,431)
Cash and cash equivalents at beginning of period	29,997	50,134
Cash and cash equivalents at end of period	32,463	46,703
Supplemental schedule of non-cash investing and financing activities:
Capital lease obligations	2,310	476
Notes issued in connection with acquisition	60
Purchases of property and equipment in accounts payable	$ 119