CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash Flows from Operating Activities:
Net income	$ 97,650	$ 77,184	$ 84,512
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	(25,703)	0	(30,840)
Depreciation and amortization	51,569	38,296	29,882
Provision for Doubtful Accounts	10,486	7,047	1,787
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for deferred income taxes	11,549	15,948	4,111
Allocated Share-based Compensation Expense	22,018	16,199	14,411
Write off of Deferred Debt Issuance Cost	3,751	0	14,958
Gross excess tax benefits from stock-based compensation	(6,551)	(4,943)	(5,308)
Workers’ compensation and medical malpractice provision	2,117	3,321	5,956
Other Noncash Income (Expense)	(7,136)	(1,408)	1,853
Changes in operating assets and liabilities, net of effects of acquisitions and divestitures:
Accounts receivable	(53,775)	(45,361)	(20,155)
Prepaid expenses and income taxes	100	(8,304)	6,628
Increase (Decrease) in Income Taxes Payable	(7,679)	(8,023)	(5,759)
Accounts payable	1,684	(1,693)	(1,580)
Accrued payroll and contract professional pay	242	11,275	17,554
Increase (Decrease) in Workers' Compensation Liabilities	(901)	(2,192)	(2,348)
Deferred compensation	0	(20)	(9,980)
Other	3,800	(4,120)	8,548
Net cash provided by operating activities	117,493	96,022	110,524
Cash Flows from Investing Activities:
Cash paid for property and equipment	(24,689)	(19,729)	(16,531)
Cash paid for acquisitions, net of cash acquired	(552,777)	0	(110,700)
Proceeds from Divestiture of Businesses, Net of Cash Divested	115,440	0	59,899
Other	496	169	(1,023)
Net cash used in investing activities	(461,530)	(19,560)	(68,355)
Cash Flows from Financing Activities:
Principal payments of long-term debt	(516,125)	(148,688)	(456,275)
Proceeds from long-term debt	875,000	164,000	429,500
Proceeds from option exercises and employee stock purchase plan	6,591	6,358	7,054
Payment of employment taxes related to release of restricted stock awards	(8,823)	(6,498)	(7,600)
Gross excess tax benefits from stock-based compensation	6,551	4,943	5,308
Repurchase of common stock	(1,645)	(100,049)	0
Debt issuance or amendment costs	(23,890)	(467)	(6,938)
Payments of accrued earn-outs	0	(691)	(3,425)
Other	0	0	(14)
Net cash provided by (used in) financing activities	337,659	(81,092)	(32,390)
Effect of exchange rate changes on cash and cash equivalents	(1,467)	(1,006)	92
Net Increase (Decrease) in Cash and Cash Equivalents	(7,845)	(5,636)	9,871
Cash and Cash Equivalents at Beginning of Year (1)	31,714	37,350	27,479
Cash and Cash Equivalents at End of Year (1)	23,869	31,714	37,350
Supplemental Disclosure of Cash Flow Information
Income taxes	45,478	56,320	32,350
Interest	22,282	11,559	15,158
Non-Cash Investing and Financing Activities:
Equity consideration for acquisition	30,183	0	0
Proceeds from Stock Options Exercised	2,174	0	0
Acquisition of property and equipment through accounts payable	$ 989	$ 2,932	$ 594