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Long-Term Debt (Schedule Of Long-Term-Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015	Dec. 15, 2009
Debt Instrument [Line Items]
Total debt	$ 993.0	$ 1,079.7
Less current maturities	96.1	168.1
Long-term debt	896.9	911.6
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total debt	100.8	136.3
North America [Member]
Debt Instrument [Line Items]
Debt discount		(257.8)
Debt issuance costs	(11.0)	(12.1)
North America [Member] \| 5.75% Senior Notes due 2022 [Member]
Debt Instrument [Line Items]
Face value	600.0	600.0
Debt issuance costs	(7.3)	(8.2)
Total debt	592.7	591.8
North America [Member] \| Subordinated Convertible Notes Due 2029 [Member]
Debt Instrument [Line Items]
Face value	429.5	429.5	$ 429.5
Debt discount	(256.2)	(257.8)
Debt issuance costs	(3.7)	(3.9)
Total debt	169.6	167.8
North America [Member] \| Other Debt [Member]
Debt Instrument [Line Items]
Total debt	9.0	9.2
North America [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total debt	66.0	127.6
Europe [Member] \| Other Debt [Member]
Debt Instrument [Line Items]
Total debt	9.2	23.4
Europe [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total debt	34.8	8.7
Latin America [Member] \| Credit Facilities [Member]
Debt Instrument [Line Items]
Total debt	103.6	113.8
Africa/Asia Pacific [Member] \| Credit Facilities [Member]
Debt Instrument [Line Items]
Total debt	$ 8.1	$ 37.4