CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Cash flows from operating activities:
Net income	$ 21,535	$ 10,534
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	16,726	17,009
Amortization of discount and deferred debt issuance costs	1,742	1,267
Share-based compensation	1,552	2,025
Deferred income taxes, net	2,347	624
Provision for losses on accounts receivable	3,343	2,885
Loss on extinguishment of debt, net of original issue discount paid		6,400
Loss on sale of assets	100	95
Changes in operating assets and liabilities	(13,279)	(16,320)
Cash provided by operating activities	34,066	24,519
Cash flows from investing activities:
Purchases of property and equipment	(8,212)	(7,415)
Acquisitions of businesses, net of cash acquired	(2,234)	(8,662)
Proceeds from sale of assets	184	43
Cash used in investing activities	(10,262)	(16,034)
Cash flows from financing activities:
Long-term debt repayments	(9,280)	(168,866)
Long-term debt borrowings		175,000
Payments on obligations under capital leases	(3,499)	(3,003)
Debt issuance costs	(2)	(3,978)
Cash used in financing activities	(12,781)	(847)
Effect of exchange rate changes on cash and cash equivalents	(81)	9
Increase in cash and cash equivalents	10,942	7,647
Cash and cash equivalents at beginning of period	50,134	25,651
Cash and cash equivalents at end of period	61,076	33,298
Supplemental schedule of non-cash investing and financing activities:
Notes issued in connection with acquisitions	336	39
Capital lease obligations	6,513	2,756
Settlement of Seller obligations in connection with an acquisition	$ 1,240