CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating activities:
Net income	$ 49,773	$ 41,013	$ 52,992
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	34,395	33,371	20,992
Amortization of discount and deferred debt issuance costs	3,481	2,961	2,943
Share-based compensation	2,917	3,836	2,383
Deferred income taxes, net	7,609	4,062	4,450
Provision for losses on accounts receivable	5,005	5,679	5,851
Loss on extinguishment of debt, net of original issue discount paid		6,400
Write down of assets held for sale			1,642
Loss on sale of assets	94	238	481
Changes in operating assets and liabilities:
Accounts receivable	(17,425)	(12,967)	(10,125)
Prepaid expenses and other current assets	(3,990)	3,013	342
Other assets	(2,197)	(3,923)	(3,657)
Accounts payable	(3,925)	(8,369)	(9,711)
Accrued expenses	5,477	(8,368)	(3,846)
Accrued income taxes	(2,066)	12,276	(10,668)
Long-term liabilities and other	(17,846)	1,099	18,543
Cash provided by operating activities	61,302	80,321	72,612
Investing activities:
Purchases of property and equipment	(20,610)	(15,485)	(13,507)
Acquisitions of businesses, net of cash acquired	(39,318)	(30,690)	(23,106)
Proceeds from sale of assets	535	166	221
Cash used in investing activities	(59,393)	(46,009)	(36,392)
Financing activities:
Long-term debt repayments	(14,709)	(174,718)	(38,824)
Long-term debt borrowings		175,000
Payments on obligations under capital leases	(7,206)	(6,034)	(92)
Debt issuance costs	(2)	(4,008)	(561)
Funds contributed by co-investors			1,400
Cash used in financing activities	(21,917)	(9,760)	(38,077)
Effect of exchange rate changes on cash and cash equivalents	(129)	(69)	(44)
(Decrease) increase in cash and cash equivalents	(20,137)	24,483	(1,901)
Cash and cash equivalents at beginning of period	50,134	25,651	27,552
Cash and cash equivalents at end of period	29,997	50,134	25,651
Cash paid for:
Interest	30,271	32,038	30,737
Income taxes (net of refunds of $0.1 million, $6.3 million and $0.3 million, respectively)	15,776	10,155	5,864
Supplemental schedule of non-cash investing and financing activities:
Notes issued in connection with acquisitions	1,110	2,374	2,138
Capital lease obligations (see Note 12)	9,763	5,752
Settlement of Seller obligations in connection with acquisitions	1,240		2,706
Purchases of property and equipment in accounts payable	$ 276