Condensed, Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013
Cash flows from operating activities:
Net income	$ 110,774	[1]	$ 117,194	[1]
Adjustments to reconcile net income to net cash provided by operating activities:
Impairment of goodwill and other long-lived assets	27,019		0
Depreciation and amortization	59,659		57,783
Amortization of debt issue costs	957		937
Provision for uncollectible accounts	4,388		5,380
Debt retirement costs	1,709		0
Net (gain) loss on sale or disposal of assets	(173)		1,187
Share-based compensation	12,234		10,340
Deferred income taxes	0		2,868
Excess tax benefit from exercise of stock options	(3,808)		(2,654)
Other	381		(251)
Changes in operating assets and liabilities:
Trade accounts receivable	(9,678)		(9,986)
Inventory, prepaid expense and other assets	(8,233)		(1,634)
Accounts payable and other accrued liabilities	2,920		4,941
Accrued payroll and related liabilities	14,761		11,408
Income taxes	12,137		21,492
Net cash provided by operating activities	225,047		219,005
Cash flows from investing activities:
Business acquisitions, net of cash acquired	(62,122)		(39,640)
Real estate acquired in connection with business acquisitions	(3,293)		(1,208)
Capital expenditures	(50,093)		(52,682)
Proceeds from sale or disposal of assets	4,464		905
Other	(202)		(1,738)
Net cash used in investing activities	(111,246)		(94,363)
Cash flows from financing activities:
Repayment of debt	(563,976)		(28,507)
Proceeds from issuance of long-term debt	600,000
Payment of financing costs	(7,987)
Distributions to noncontrolling interest partners	(3,577)		(3,324)
Purchase of existing noncontrolling interests	(326)		(5,727)
Proceeds from issuance of common stock under stock option plans	926		15,111
Excess tax benefit from exercise of stock options	3,808		2,654
Repurchase of common stock	(139,910)		(19,384)
Other	(838)		(160)
Net cash used in financing activities	(111,880)		(39,337)
Effect of currency exchange rate changes on cash and cash equivalents	(443)		(566)
Increase in cash and cash equivalents	1,478		84,739
Cash and cash equivalents at beginning of period	125,029		68,435
Cash and cash equivalents at end of period	126,507		153,174
Supplemental disclosures of cash flow information:
Interest paid	10,633		9,487
Income taxes paid	57,108		47,305
Detail of acquisitions:
Fair value of assets acquired	76,686		58,825
Fair value of pre-existing investment	(2,014)		0
Noncontrolling interest	(1,705)		(5,406)
Cash paid for acquisitions, net of acquired cash	(62,122)		(39,640)
Assumed debt	(4,483)		(2,360)
Contingent consideration	(2,531)		(1,120)
Holdbacks	(2,900)		(892)
Other liabilities assumed	931		9,407
Capital lease additions	$ 0		$ 21,668

[1] Includes approximately $1.9 million and $2.6 million of net income related to redeemable and mandatorily redeemable noncontrolling interests combined for the nine months ended September 30, 2014 and 2013, respectively.