Consolidated Statements of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Operating activities:
Net loss	$ (14,939,000)	$ (8,333,000)	$ (6,038,000)
Adjustments to reconcile net loss to net cash provided by operating activities:
(Gain) loss on interest rate swap	(225,000)	(328,000)	42,000
Depreciation and amortization	58,551,000	47,439,000	19,505,000
Amortization of deferred rent	(82,000)	(450,000)	(61,000)
Share-based compensation	13,756,000	7,834,000	1,816,000
Excess tax benefit related to share-based compensation	(2,853,000)		(974,000)
Provision for doubtful accounts	2,852,000	2,297,000	173,000
Amortization of deferred financing costs	2,190,000	1,941,000	872,000
Deferred income taxes	(21,201,000)	(6,364,000)	(5,406,000)
Loss on early extinguishment of debt		621,000	3,169,000
Other	(31,000)
Changes in operating assets and liabilities, net of effects of acquisitions:
Accounts receivable	(24,666,000)	(9,047,000)	(2,098,000)
Prepaid expenses and other current assets	(64,000)	(1,801,000)	560,000
Accounts payable and accrued expenses	8,300,000	(1,907,000)	5,946,000
Accrued interest expense	671,000	10,240,000
Deferred revenue and customer deposits	2,425,000	(169,000)	(917,000)
Other liabilities	93,000	(2,430,000)	1,714,000
Net cash provided by operating activities	24,777,000	39,543,000	18,303,000
Investing activities:
Cash paid for acquisitions, net	(108,970,000)	(322,248,000)	(115,225,000)
Purchases of equipment and leasehold improvements, net	(5,841,000)	(6,856,000)	(1,730,000)
Working capital and other settlements for acquisitions	427,000	(6,710,000)	418,000
Net cash used in investing activities	(114,384,000)	(335,814,000)	(116,537,000)
Financing activities:
Borrowings under credit facilities	170,640,000	278,000,000	67,315,000
Excess tax benefit related to share-based compensation	2,853,000		974,000
Proceeds from the exercise of options and warrants	2,258,000	2,292,000	703,000
Borrowings under senior unsecured notes payable		250,000,000
Issuance of preferred stock, net			32,421,000
Issuance of common stock, net			136,660,000
Repayment of related party notes			(3,500,000)
Purchases of stock for treasury	(387,000)	(9,421,000)
Payment of deferred financing costs	(1,074,000)	(9,746,000)	(6,534,000)
Repayment of subordinated unsecured notes payable	(2,193,000)	(2,421,000)	(2,167,000)
Net borrowings (repayments) under working capital facilities	(6,279,000)	35,621,000	4,997,000
Repayment under credit facilities	(76,000,000)	(273,000,000)	(100,550,000)
Other	(94,000)	(440,000)
Net cash provided by financing activities	89,724,000	270,885,000	130,319,000
Exchange rate impact on cash and cash equivalents	94,000	178,000	40,000
Net increase (decrease) in cash and cash equivalents	211,000	(25,208,000)	32,125,000
Cash and cash equivalents, beginning of year	8,416,000	33,624,000	1,499,000
Cash and cash equivalents, end of year	8,627,000	8,416,000	33,624,000
Supplemental disclosure of noncash investing and financing activities:
Issuance of subordinated unsecured notes payable for acquisitions			1,747,000
Issuance of common stock to settle earnout obligations		808,000	576,000
Issuance of common stock for termination of agreement			1,434,000
Supplemental disclosures of cash flow information:
Cash paid for interest	25,214,000	5,447,000	4,994,000
Cash paid for income taxes	8,913,000	4,061,000	231,000
Issuance Of Common Stock For Acquisitions [Member]
Supplemental disclosure of noncash investing and financing activities:
Issuance of common stock for acquisitions	$ 85,000	$ 47,174,000	$ 10,075,000