Financial Information for Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Supplemental Condensed Consolidating Statement of Cash Flows) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Condensed Financial Statements
Net cash provided by (used in) operating activities	$ 255.5	$ 233.4
Cash flows from investing activities:
Capital expenditures	(233.6)	(176.3)
Proceeds from (Payments for) Interests in Joint Ventures		(43.3)
Distributions of capital on equity investments	37.0	45.4
Proceeds from Sale of Equity Method Investments	9.3	44.9
Payments for (Proceeds from) Other Investing Activities	10.1	(0.6)
Other, principally intercompany balances	0.0	0.0
Net cash used in investing activities	(177.2)	(129.9)
Cash flows from financing activities:
Net proceeds/payments on long-term debt	(108.8)	(52.2)
Payments on license obligations	32.0	7.0
Payments of license obligations		(7.0)
Common stock repurchases	0.0	(29.5)
Contingent earnout payments	(0.5)	(10.2)
Cash flows from financing activities:	0.4	(19.1)
Other, principally intercompany balances	0.0	0.0
Net cash provided by (used in) financing activities	(140.9)	(118.0)
Cash and cash equivalents, end of period	102.1	132.5
Effect of exchange rate changes on cash and cash equivalents	(7.1)	(6.7)
Net Cash Provided by (Used in) Continuing Operations	(69.7)	(21.2)
Parent Company
Condensed Financial Statements
Net cash provided by (used in) operating activities	(11.5)	(79.2)
Cash flows from investing activities:
Capital expenditures	(12.8)	(8.4)
Proceeds from (Payments for) Interests in Joint Ventures		0.0
Distributions of capital on equity investments	0.0	0.0
Proceeds from Sale of Equity Method Investments	0.0	0.0
Payments for (Proceeds from) Other Investing Activities	0.0	(9.6)
Other, principally intercompany balances	0.0	0.0
Net cash used in investing activities	(12.8)	(18.0)
Cash flows from financing activities:
Net proceeds/payments on long-term debt	0.0	0.0
Payments on license obligations	19.5
Payments of license obligations		0.0
Common stock repurchases		(29.5)
Contingent earnout payments	0.0	0.0
Cash flows from financing activities:	0.5	(19.1)
Other, principally intercompany balances	22.7	126.2
Net cash provided by (used in) financing activities	3.7	77.6
Cash and cash equivalents, end of period	17.3	36.4
Effect of exchange rate changes on cash and cash equivalents	0.0	0.0
Net Cash Provided by (Used in) Continuing Operations	(20.6)	(19.6)
SGI
Condensed Financial Statements
Net cash provided by (used in) operating activities	44.3	19.8
Cash flows from investing activities:
Capital expenditures	(19.7)	(23.9)
Proceeds from (Payments for) Interests in Joint Ventures		0.0
Distributions of capital on equity investments	1.0	(1.3)
Proceeds from Sale of Equity Method Investments	0.0	0.0
Payments for (Proceeds from) Other Investing Activities	(0.1)	29.2
Other, principally intercompany balances	77.2	18.8
Net cash used in investing activities	58.4	22.8
Cash flows from financing activities:
Net proceeds/payments on long-term debt	(102.3)	(42.3)
Payments on license obligations	0.0
Payments of license obligations		0.0
Common stock repurchases		0.0
Contingent earnout payments	0.0	0.0
Cash flows from financing activities:	0.0	0.0
Other, principally intercompany balances	0.0	0.0
Net cash provided by (used in) financing activities	(102.3)	(42.3)
Cash and cash equivalents, end of period	0.0	0.3
Effect of exchange rate changes on cash and cash equivalents	(0.5)	0.0
Net Cash Provided by (Used in) Continuing Operations	(0.1)	0.3
Guarantor Subsidiaries
Condensed Financial Statements
Net cash provided by (used in) operating activities	85.2	160.0
Cash flows from investing activities:
Capital expenditures	(169.9)	(113.3)
Proceeds from (Payments for) Interests in Joint Ventures		0.0
Distributions of capital on equity investments	0.0	0.0
Proceeds from Sale of Equity Method Investments	9.3	0.0
Payments for (Proceeds from) Other Investing Activities	5.1	(0.6)
Other, principally intercompany balances	0.0	(44.9)
Net cash used in investing activities	(155.5)	(158.8)
Cash flows from financing activities:
Net proceeds/payments on long-term debt	0.0	0.0
Payments on license obligations	12.5
Payments of license obligations		(7.0)
Common stock repurchases		0.0
Contingent earnout payments	(0.5)	(7.0)
Cash flows from financing activities:	(37.1)	0.0
Other, principally intercompany balances	99.0	0.0
Net cash provided by (used in) financing activities	48.9	(14.0)
Cash and cash equivalents, end of period	6.8	11.3
Effect of exchange rate changes on cash and cash equivalents	(0.6)	(0.3)
Net Cash Provided by (Used in) Continuing Operations	(22.0)	(13.1)
Non-Guarantor Subsidiaries
Condensed Financial Statements
Net cash provided by (used in) operating activities	137.5	132.8
Cash flows from investing activities:
Capital expenditures	(31.2)	(30.7)
Proceeds from (Payments for) Interests in Joint Ventures		(43.3)
Distributions of capital on equity investments	36.0	46.7
Proceeds from Sale of Equity Method Investments	0.0	44.9
Payments for (Proceeds from) Other Investing Activities	5.1	16.1
Other, principally intercompany balances	0.0	0.0
Net cash used in investing activities	9.9	33.7
Cash flows from financing activities:
Net proceeds/payments on long-term debt	(6.5)	(9.9)
Payments on license obligations	0.0
Payments of license obligations		0.0
Common stock repurchases		0.0
Contingent earnout payments	0.0	(3.2)
Cash flows from financing activities:	(110.2)	(35.7)
Other, principally intercompany balances	(51.7)	(100.1)
Net cash provided by (used in) financing activities	(168.4)	(148.9)
Cash and cash equivalents, end of period	78.0	84.5
Effect of exchange rate changes on cash and cash equivalents	(6.0)	(6.4)
Net Cash Provided by (Used in) Continuing Operations	(27.0)	11.2
Eliminating Entries
Condensed Financial Statements
Net cash provided by (used in) operating activities	0.0	0.0
Cash flows from investing activities:
Capital expenditures	0.0	0.0
Proceeds from (Payments for) Interests in Joint Ventures		0.0
Distributions of capital on equity investments	0.0	0.0
Proceeds from Sale of Equity Method Investments	0.0	0.0
Payments for (Proceeds from) Other Investing Activities	0.0	(35.7)
Other, principally intercompany balances	(77.2)	26.1
Net cash used in investing activities	(77.2)	(9.6)
Cash flows from financing activities:
Net proceeds/payments on long-term debt	0.0	0.0
Payments on license obligations	0.0
Payments of license obligations		0.0
Common stock repurchases		0.0
Contingent earnout payments	0.0	0.0
Cash flows from financing activities:	147.2	35.7
Other, principally intercompany balances	(70.0)	(26.1)
Net cash provided by (used in) financing activities	77.2	9.6
Cash and cash equivalents, end of period	0.0	0.0
Effect of exchange rate changes on cash and cash equivalents	0.0	0.0
Net Cash Provided by (Used in) Continuing Operations	$ 0.0	$ 0.0