Financial Information for Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Supplemental Condensed Consolidating Statement of Cash Flows) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Condensed Financial Statements
Net cash provided by (used in) operating activities	$ 114.4	$ 107.1
Cash flows from investing activities:
Capital expenditures	(142.8)	(114.7)
Proceeds from (Payments for) Interests in Joint Ventures		(40.6)
Distributions of capital on equity investments	35.2	32.9
Proceeds from Sale of Equity Method Investments	0.0	44.9
Payments for (Proceeds from) Other Investing Activities	9.5	(1.1)
Other, principally intercompany balances	0.0	0.0
Net cash used in investing activities	(98.1)	(78.6)
Cash flows from financing activities:
Net proceeds/payments on long-term debt	(36.2)	(16.8)
Payments on license obligations	18.7	0.0
Payments of financing fees	0.0	22.8
Common stock repurchases	0.0	(29.5)
Contingent earnout payments	(0.5)	(3.2)
Cash flows from financing activities:	0.9	(19.2)
Other, principally intercompany balances	0.0	0.0
Net cash provided by (used in) financing activities	(54.5)	(91.5)
Cash and cash equivalents, end of period	129.1	89.2
Effect of exchange rate changes on cash and cash equivalents	(4.5)	(1.5)
Net Cash Provided by (Used in) Continuing Operations	(42.7)	(64.5)
Parent Company
Condensed Financial Statements
Net cash provided by (used in) operating activities	(33.1)	(54.6)
Cash flows from investing activities:
Capital expenditures	(8.6)	(6.0)
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
Payments for (Proceeds from) Other Investing Activities	0.0	0.0
Other, principally intercompany balances	0.0	0.0
Net cash used in investing activities	(8.6)	(6.0)
Cash flows from financing activities:
Net proceeds/payments on long-term debt	0.0	0.0
Payments on license obligations	13.5
Payments of financing fees		0.0
Common stock repurchases		(29.5)
Contingent earnout payments	0.0	0.0
Cash flows from financing activities:	0.9	(19.2)
Other, principally intercompany balances	58.2	69.6
Net cash provided by (used in) financing activities	45.6	20.9
Cash and cash equivalents, end of period	41.9	16.3
Effect of exchange rate changes on cash and cash equivalents	0.1	0.0
Net Cash Provided by (Used in) Continuing Operations	4.0	(39.7)
SGI
Condensed Financial Statements
Net cash provided by (used in) operating activities	(69.4)	8.8
Cash flows from investing activities:
Capital expenditures	(12.4)	(16.1)
Proceeds from (Payments for) Interests in Joint Ventures		0.0
Distributions of capital on equity investments	0.8	1.1
Proceeds from Sale of Equity Method Investments		0.0
Payments for (Proceeds from) Other Investing Activities	0.0	22.0
Other, principally intercompany balances	114.2	20.9
Net cash used in investing activities	102.6	27.9
Cash flows from financing activities:
Net proceeds/payments on long-term debt	(31.5)	(13.8)
Payments on license obligations	0.0
Payments of financing fees		22.8
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	(31.5)	(36.6)
Cash and cash equivalents, end of period	1.4	0.1
Effect of exchange rate changes on cash and cash equivalents	(0.4)	0.0
Net Cash Provided by (Used in) Continuing Operations	1.3	0.1
Guarantor Subsidiaries
Condensed Financial Statements
Net cash provided by (used in) operating activities	127.7	62.7
Cash flows from investing activities:
Capital expenditures	(95.6)	(67.6)
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
Payments for (Proceeds from) Other Investing Activities	4.0	(1.3)
Other, principally intercompany balances	0.0	(16.2)
Net cash used in investing activities	(91.6)	(85.1)
Cash flows from financing activities:
Net proceeds/payments on long-term debt	0.0	0.0
Payments on license obligations	5.2
Payments of financing fees		0.0
Common stock repurchases		0.0
Contingent earnout payments	(0.5)	0.0
Cash flows from financing activities:	(29.6)	0.0
Other, principally intercompany balances	(12.0)	0.0
Net cash provided by (used in) financing activities	(47.3)	0.0
Cash and cash equivalents, end of period	15.8	1.3
Effect of exchange rate changes on cash and cash equivalents	(1.8)	(0.7)
Net Cash Provided by (Used in) Continuing Operations	(13.0)	(23.1)
Non-Guarantor Subsidiaries
Condensed Financial Statements
Net cash provided by (used in) operating activities	89.2	90.2
Cash flows from investing activities:
Capital expenditures	(26.2)	(25.0)
Proceeds from (Payments for) Interests in Joint Ventures		(40.6)
Distributions of capital on equity investments	34.4	31.8
Proceeds from Sale of Equity Method Investments		44.9
Payments for (Proceeds from) Other Investing Activities	5.5	5.9
Other, principally intercompany balances	0.0	0.0
Net cash used in investing activities	13.7	17.0
Cash flows from financing activities:
Net proceeds/payments on long-term debt	(4.7)	(3.0)
Payments on license obligations	0.0
Payments of financing fees		0.0
Common stock repurchases		0.0
Contingent earnout payments	0.0	(3.2)
Cash flows from financing activities:	(116.0)	(27.7)
Other, principally intercompany balances	(14.8)	(74.3)
Net cash provided by (used in) financing activities	(135.5)	(108.2)
Cash and cash equivalents, end of period	70.0	71.5
Effect of exchange rate changes on cash and cash equivalents	(2.4)	(0.8)
Net Cash Provided by (Used in) Continuing Operations	(35.0)	(1.8)
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
Payments for (Proceeds from) Other Investing Activities	0.0	(27.7)
Other, principally intercompany balances	(114.2)	(4.7)
Net cash used in investing activities	(114.2)	(32.4)
Cash flows from financing activities:
Net proceeds/payments on long-term debt	0.0	0.0
Payments on license obligations	0.0
Payments of financing fees		0.0
Common stock repurchases		0.0
Contingent earnout payments	0.0	0.0
Cash flows from financing activities:	145.6	27.7
Other, principally intercompany balances	(31.4)	4.7
Net cash provided by (used in) financing activities	114.2	32.4
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