Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net income	$ 252.8	$ 281.7	$ 381.4
Loss (income) from discontinued operations, net of tax	0.9	(5.5)	1.1
Adjustments to reconcile net income to net cash provided by operating activities-
Provision for doubtful accounts	47.2	31.6	26.0
Provision for government, class action, and related settlements	7.5	(1.7)	(23.5)
Depreciation and amortization	139.7	107.7	94.7
Amortization of debt-related items	14.3	12.7	5.0
Loss on early extinguishment of debt	22.4	13.2	2.4
Equity in net income of nonconsolidated affiliates	(8.7)	(10.7)	(11.2)
Distributions from nonconsolidated affiliates	7.7	12.6	11.4
Stock-based compensation	26.2	23.9	24.8
Deferred tax expense	127.1	97.4	6.4
Gain on consolidation of Fairlawn	0.0	(27.2)	0.0
Other	(0.6)	4.8	4.3
(Increase) decrease in assets, net of acquisitions-
Accounts receivable	(134.1)	(91.6)	(55.1)
Prepaid expenses and other assets	(9.6)	6.5	(4.8)
Increase (decrease) in liabilities, net of acquisitions-
Accounts payable	0.9	5.4	6.4
Other liabilities	(4.3)	(10.4)	4.6
Premium received on bond issuance	9.8	6.3	0.0
Premium paid on redemption of bonds	(13.7)	(10.6)	(1.7)
Net cash used in operating activities of discontinued operations	(0.7)	(1.2)	(1.9)
Total adjustments	231.1	168.7	87.8
Net cash provided by operating activities	484.8	444.9	470.3
Cash flows from investing activities:
Acquisition of businesses, net of cash acquired	(985.1)	(694.8)	(28.9)
Purchases of property and equipment	(128.4)	(170.9)	(195.2)
Capitalized software costs	(28.1)	(17.0)	(21.3)
Proceeds from sale of restricted investments	0.2	0.3	16.9
Proceeds from sale of Digital Hospital	0.0	0.0	10.8
Proceeds from sale of marketable securities	12.8	0.0	0.0
Purchases of restricted investments	(7.1)	(3.5)	(9.2)
Net change in restricted cash	2.7	6.8	(3.1)
Other	2.7	2.2	0.5
Net cash provided by investing activities of discontinued operations	0.5	0.0	3.3
Net cash used in investing activities	(1,129.8)	(876.9)	(226.2)
Cash flows from financing activities:
Principal borrowings on term loan facilities	250.0	450.0	0.0
Proceeds from bond issuance	1,400.0	175.0	0.0
Principal payments on debt, including pre-payments	(597.4)	(302.6)	(62.5)
Principal borrowings on notes	0.0	0.0	15.2
Borrowings on revolving credit facility	540.0	440.0	197.0
Payments on revolving credit facility	(735.0)	(160.0)	(152.0)
Principal payments under capital lease obligations	(11.0)	(6.1)	(10.1)
Debt amendment and issuance costs	(31.9)	(6.5)	(2.6)
Repurchase of common stock, including fees and expenses	(45.3)	(43.1)	(234.1)
Dividends paid on common stock	(77.2)	(65.8)	(15.7)
Dividends paid on convertible perpetual preferred stock	(3.1)	(6.3)	(23.0)
Distributions paid to noncontrolling interests of consolidated affiliates	(54.4)	(54.1)	(46.3)
Proceeds from exercising stock warrants	0.0	6.3	15.3
Other	5.2	7.4	6.4
Net cash provided by (used in) financing activities	639.9	434.2	(312.4)
(Decrease) increase in cash and cash equivalents	(5.1)	2.2	(68.3)
Cash and cash equivalents at beginning of year	66.7	64.5	132.8
Cash and cash equivalents at end of year	61.6	66.7	64.5
Cash (paid) received during the year for-
Interest	(121.4)	(100.6)	(99.4)
Income tax refunds	7.4	1.3	4.8
Income tax payments	(16.8)	(17.7)	(12.5)
Supplemental schedule of noncash investing and financing activities: [Abstract]
Convertible debt issued	0.0	0.0	320.0
Repurchase of preferred stock	0.0	0.0	(320.0)
Equity rollover from Encompass management	0.0	64.5	0.0
Preferred stock conversion	$ 93.2	$ 0.0	$ 0.0