Supplemental Guarantor Information Supplemental Guarantor Information (Condensed Consolidating Statement of Cash Flows) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Net cash used by operating activities		$ (67.6)	$ (256.6)
Cash flow from investing activities:
Capital expenditures		(20.3)	(30.6)
Payments for acquisitions	$ (5.8)	0.0	(5.8)
Proceeds from maturities of short-term investments		108.2	158.5
Payments for purchases of short-term investments		(85.8)	(91.1)
Proceeds from sale of assets		8.2	10.5
Increase in certain other assets		(11.8)	(17.2)
Capital contributions and loans paid		0.0	0.0
Proceeds from intercompany loans		0.0	0.0
Net cash used by investing activities		(1.5)	24.3
Cash flow from financing activities:
Dividends paid		0.0	(7.7)
Revolving credit facility (repayments) borrowings, net		(10.0)	65.0
Other debt borrowings		19.6	34.2
Other debt repayments		(42.9)	(57.6)
Distributions and payments to noncontrolling interest holders		(98.0)	(29.1)
Repurchase of common shares and other		(1.6)	(2.9)
Capital contributions received and loans incurred		0.0	0.0
Payments on intercompany loans		0.0	0.0
Net cash provided by financing activities		(132.9)	1.0
Effect of exchange rate changes on cash and cash equivalents		0.2	(9.8)
Increase (decrease) in cash, cash equivalents and restricted cash		(201.8)	(241.1)
Add: Cash included in assets held for sale at beginning of period	0.0	7.3	0.0
Less: Cash included in assets held for sale at end of period		4.1	0.0
Cash, cash equivalents and restricted cash at the beginning of the period	543.2	458.4	543.2
Cash, cash equivalents and restricted cash at the end of the period		259.8	302.1
Payments of Debt Issuance Costs		0.0	0.9
Reportable Legal Entities [Member] | Parent Company [Member]
Net cash used by operating activities		54.7	(8.3)
Cash flow from investing activities:
Capital expenditures		(2.2)	(3.8)
Payments for acquisitions			0.0
Proceeds from maturities of short-term investments		1.2	2.4
Payments for purchases of short-term investments		0.0	0.0
Proceeds from sale of assets		0.1	6.7
Increase in certain other assets		(3.4)	(4.0)
Capital contributions and loans paid		(27.4)	(27.3)
Proceeds from intercompany loans		9.9	18.9
Net cash used by investing activities		(21.8)	(7.1)
Cash flow from financing activities:
Dividends paid			(7.7)
Revolving credit facility (repayments) borrowings, net		(25.0)	0.0
Other debt borrowings		0.0	0.0
Other debt repayments		(13.6)	(22.6)
Distributions and payments to noncontrolling interest holders		0.0	0.0
Repurchase of common shares and other		(1.6)	(2.9)
Capital contributions received and loans incurred		0.0	0.0
Payments on intercompany loans		0.0	0.0
Net cash provided by financing activities		(40.2)	(34.1)
Effect of exchange rate changes on cash and cash equivalents		0.0	0.0
Increase (decrease) in cash, cash equivalents and restricted cash		(7.3)	(49.5)
Add: Cash included in assets held for sale at beginning of period		0.0
Less: Cash included in assets held for sale at end of period		0.0
Cash, cash equivalents and restricted cash at the beginning of the period	58.5	17.3	58.5
Cash, cash equivalents and restricted cash at the end of the period		10.0	9.0
Payments of Debt Issuance Costs			0.9
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Net cash used by operating activities		(21.0)	(12.5)
Cash flow from investing activities:
Capital expenditures		0.0	(0.1)
Payments for acquisitions			0.0
Proceeds from maturities of short-term investments		0.0	0.0
Payments for purchases of short-term investments		0.0	0.0
Proceeds from sale of assets		0.0	0.0
Increase in certain other assets		0.0	0.0
Capital contributions and loans paid		0.0	0.0
Proceeds from intercompany loans		0.0	0.0
Net cash used by investing activities		0.0	(0.1)
Cash flow from financing activities:
Dividends paid			0.0
Revolving credit facility (repayments) borrowings, net		0.0	0.0
Other debt borrowings		0.0	0.0
Other debt repayments		0.0	(0.2)
Distributions and payments to noncontrolling interest holders		0.0	0.0
Repurchase of common shares and other		0.0	0.0
Capital contributions received and loans incurred		27.0	27.3
Payments on intercompany loans		(6.8)	(13.5)
Net cash provided by financing activities		20.2	13.6
Effect of exchange rate changes on cash and cash equivalents		0.0	0.0
Increase (decrease) in cash, cash equivalents and restricted cash		(0.8)	1.0
Add: Cash included in assets held for sale at beginning of period		0.0
Less: Cash included in assets held for sale at end of period		0.0
Cash, cash equivalents and restricted cash at the beginning of the period	2.3	2.7	2.3
Cash, cash equivalents and restricted cash at the end of the period		1.9	3.3
Payments of Debt Issuance Costs			0.0
Reportable Legal Entities [Member] | Foreign Guarantor Subsidiary [Member]
Net cash used by operating activities		0.0	(0.2)
Cash flow from investing activities:
Capital expenditures		0.0	0.0
Payments for acquisitions			0.0
Proceeds from maturities of short-term investments		0.0	0.0
Payments for purchases of short-term investments		0.0	0.0
Proceeds from sale of assets		0.0	0.0
Increase in certain other assets		0.0	0.0
Capital contributions and loans paid		0.0	0.0
Proceeds from intercompany loans		0.0	0.0
Net cash used by investing activities		0.0	0.0
Cash flow from financing activities:
Dividends paid			0.0
Revolving credit facility (repayments) borrowings, net		0.0	0.0
Other debt borrowings		0.0	0.0
Other debt repayments		0.0	0.0
Distributions and payments to noncontrolling interest holders		0.0	0.0
Repurchase of common shares and other		0.0	0.0
Capital contributions received and loans incurred		0.0	0.0
Payments on intercompany loans		0.0	0.0
Net cash provided by financing activities		0.0	0.0
Effect of exchange rate changes on cash and cash equivalents		0.0	0.0
Increase (decrease) in cash, cash equivalents and restricted cash		0.0	(0.2)
Add: Cash included in assets held for sale at beginning of period		0.0
Less: Cash included in assets held for sale at end of period		0.0
Cash, cash equivalents and restricted cash at the beginning of the period	0.2	0.0	0.2
Cash, cash equivalents and restricted cash at the end of the period		0.0	0.0
Payments of Debt Issuance Costs			0.0
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Net cash used by operating activities		(101.3)	(235.6)
Cash flow from investing activities:
Capital expenditures		(18.1)	(26.7)
Payments for acquisitions			(5.8)
Proceeds from maturities of short-term investments		107.0	156.1
Payments for purchases of short-term investments		(85.8)	(91.1)
Proceeds from sale of assets		8.1	3.8
Increase in certain other assets		(8.4)	(13.2)
Capital contributions and loans paid		0.0	0.0
Proceeds from intercompany loans		0.0	0.0
Net cash used by investing activities		2.8	23.1
Cash flow from financing activities:
Dividends paid			0.0
Revolving credit facility (repayments) borrowings, net		15.0	65.0
Other debt borrowings		19.6	34.2
Other debt repayments		(29.3)	(34.8)
Distributions and payments to noncontrolling interest holders		(98.0)	(29.1)
Repurchase of common shares and other		0.0	0.0
Capital contributions received and loans incurred		0.4	0.0
Payments on intercompany loans		(3.1)	(5.4)
Net cash provided by financing activities		(95.4)	29.9
Effect of exchange rate changes on cash and cash equivalents		0.2	(9.8)
Increase (decrease) in cash, cash equivalents and restricted cash		(193.7)	(192.4)
Add: Cash included in assets held for sale at beginning of period		7.3
Less: Cash included in assets held for sale at end of period		4.1
Cash, cash equivalents and restricted cash at the beginning of the period	482.2	438.4	482.2
Cash, cash equivalents and restricted cash at the end of the period		247.9	289.8
Payments of Debt Issuance Costs			0.0
Consolidation, Eliminations [Member]
Net cash used by operating activities		0.0	0.0
Cash flow from investing activities:
Capital expenditures		0.0	0.0
Payments for acquisitions			0.0
Proceeds from maturities of short-term investments		0.0	0.0
Payments for purchases of short-term investments		0.0	0.0
Proceeds from sale of assets		0.0	0.0
Increase in certain other assets		0.0	0.0
Capital contributions and loans paid		27.4	27.3
Proceeds from intercompany loans		(9.9)	(18.9)
Net cash used by investing activities		17.5	8.4
Cash flow from financing activities:
Dividends paid			0.0
Revolving credit facility (repayments) borrowings, net		0.0	0.0
Other debt borrowings		0.0	0.0
Other debt repayments		0.0	0.0
Distributions and payments to noncontrolling interest holders		0.0	0.0
Repurchase of common shares and other		0.0	0.0
Capital contributions received and loans incurred		(27.4)	(27.3)
Payments on intercompany loans		9.9	18.9
Net cash provided by financing activities		(17.5)	(8.4)
Effect of exchange rate changes on cash and cash equivalents		0.0	0.0
Increase (decrease) in cash, cash equivalents and restricted cash		0.0	0.0
Add: Cash included in assets held for sale at beginning of period		0.0
Less: Cash included in assets held for sale at end of period		0.0
Cash, cash equivalents and restricted cash at the beginning of the period	$ 0.0	0.0	0.0
Cash, cash equivalents and restricted cash at the end of the period		$ 0.0	0.0
Payments of Debt Issuance Costs			$ 0.0