Segment information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Segment Revenue and Operating Profit [Line Items]
Revenues	$ 997.1	$ 995.8	$ 979.3	$ 913.3	$ 880.6	$ 776.1	$ 729.4	$ 735.4	$ 3,885.5	$ 3,121.5	$ 3,135.0
Operating profit	51.4	62.5	20.4	37.0	46.9	44.1	31.5	23.8	171.3	146.3	166.8
Capital expenditures	77.5	47.1	42.2	29.4	46.3	41.3	34.3	26.9	196.2	148.8	170.6
Depreciation									151.5	127.5	125.1
Depreciation and amortization	41.9	40.5	41.2	38.8	36.6	34.8	32.9	32.3	162.4	136.6	135.1
Total assets	2,406.2				2,270.5				2,406.2	2,270.5	1,879.8
Long-Lived Assets and Revenues [Line Items]
Long-Lived Assets	1,044.4				1,026.4				1,044.4	1,026.4	832.6
Venezuelan Revenues									3,885.5	3,121.5	3,135.0
Net Assets Outside Us [Line Items]
Net assets	692.4				787.6				692.4	787.6	684.6
Unconsolidated Equity Affiliates held by International Segment [Abstract]
Carrying value of investments at year end	12.8				11.5				12.8	11.5
Share of earnings of unconsolidated equity affiliates									4.8	3.9	4.5
Europe, Middle East and Africa [Member]
Net Assets Outside Us [Line Items]
Net assets	285.2				271.2				285.2	271.2	300.9
Latin America [Member]
Net Assets Outside Us [Line Items]
Net assets	376.9				346.4				376.9	346.4	261.1
Asia Pacific [Member]
Net Assets Outside Us [Line Items]
Net assets	98.6				94.8				98.6	94.8	87.8
Other [Member]
Net Assets Outside Us [Line Items]
Net assets	(68.3)				75.2				(68.3)	75.2	34.8
International Segment [Member]
Unconsolidated Equity Affiliates held by International Segment [Abstract]
Carrying value of investments at year end	12.8				11.5				12.8	11.5	10.2
Share of earnings of unconsolidated equity affiliates									4.8	3.9	4.5
Undistributed earnings of equity affiliates included in consolidated retained earrings [Abstract]
Undistributed earnings	7.1				5.7				7.1	5.7	5.3
France [Member]
Long-Lived Assets and Revenues [Line Items]
Long-Lived Assets	149.9				159.9				149.9	159.9	167.2
Venezuelan Revenues									567.2	533.0	615.2
Mexico [Member]
Long-Lived Assets and Revenues [Line Items]
Long-Lived Assets	123.9				118.5				123.9	118.5	0
Venezuelan Revenues									415.2	51.7	0
Brazil [Member]
Long-Lived Assets and Revenues [Line Items]
Long-Lived Assets	100.9				99.8				100.9	99.8	96.5
Venezuelan Revenues									386.8	303.3	257.6
Venezuela [Member]
Long-Lived Assets and Revenues [Line Items]
Long-Lived Assets	43.5				38.3				43.5	38.3	33.2
Venezuelan Revenues									269.2	185.9	376.1
Other [Member]
Long-Lived Assets and Revenues [Line Items]
Long-Lived Assets	425.4				424.5				425.4	424.5	372.8
Venezuelan Revenues									1,513.6	1,304.1	1,154.5
Non-U.S. [Member]
Long-Lived Assets and Revenues [Line Items]
Long-Lived Assets	843.6				841.0				843.6	841.0	669.7
Venezuelan Revenues									3,152.0	2,378.0	2,403.4
United States [Member]
Long-Lived Assets and Revenues [Line Items]
Long-Lived Assets	200.8				185.4				200.8	185.4	162.9
Venezuelan Revenues									733.5	743.5	731.6
International [Member]
Segment Revenue and Operating Profit [Line Items]
Revenues									2,911.3	2,203.7	2,240.9
Operating profit									199.7	164.8	156.8
Capital expenditures									144.8	110.7	103.1
Depreciation									96.9	84.5	88.5
Amortization									8.9	8.1	9.0
Total assets	1,565.9				1,531.7				1,565.9	1,531.7	1,265.5
North America [Member]
Segment Revenue and Operating Profit [Line Items]
Revenues									974.2	917.8	894.1
Operating profit									31.4	44.1	56.6
Capital expenditures									51.4	38.1	67.5
Depreciation									54.6	43.0	36.6
Amortization									2.0	1.0	1.0
Total assets	468.6				426.8				468.6	426.8	335.4
Segment operating profit [Member]
Segment Revenue and Operating Profit [Line Items]
Operating profit									231.1	208.9	213.4
Total assets	2,034.5				1,958.5				2,034.5	1,958.5	1,600.9
Non Segment [Member]
Segment Revenue and Operating Profit [Line Items]
Operating profit									(59.8)	(62.6)	(46.6)
Total assets	$ 371.7				$ 312.0				$ 371.7	$ 312.0	$ 278.9