Income tax (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
U.S. federal	$ 82.6	$ 59.7	$ 51.3
Foreign	31.2	30.9	27.4
State and local	11.3	5.9	4.9
Total current tax expense	125.1	96.5	83.6
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Total deferred tax expense	(0.5)	2.0	8.7
Provision for income taxes	124.6	97.2	92.3
Dividend out of current earnings from foreign subsidiaries to U.S. parent company	170.0
Foreign Tax Credit Associated with Dividends from Foreign Subsidiaries	8.0
2013 Dividend Out Of Current Earnings From Brazilian Subsidiary to U.S. Parent Company		21.3
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0.4	1.0	0.6
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount		8.9
Foreign Tax Credit Associated with Dividend from Brazil		8.0
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
U.S. income before income taxes	255.3	201.1	203.7
Non-U.S. income before income taxes	108.4	88.6	37.5
Income from continuing operations before income taxes	363.7	289.7	241.2
Components of Deferred Tax Assets [Abstract]
Accounts receivable, principally due to allowances for returns and doubtful accounts	5.5	9.0
Inventories, principally due to additional costs inventories for tax purposes	24.1	30.8
Employee compensation and benefits accrued for financial reporting purposes	88.1	51.6
Foreign net operating losses	22.8	26.8
Foreign tax credits	25.0	17.0
Other	13.4	16.8
Total deferred tax assets	178.9	152.0
Less valuation allowance	(47.9)	(42.1)
Total deferred tax assets after valuation allowance	131.0	109.9
Components of Deferred Tax Liabilities [Abstract]
Plant and equipment, principally due to differences in depreciation, capitalized interest, and capitalized overhead	116.9	124.4
Goodwill and intangible assets, principally due to differences in amortization	172.1	175.3
Total deferred tax liabilities	289.0	299.7
Deferred tax liabilities, net	158.0	189.8
Deferred Tax Assets, Net, Classification [Abstract]
Deferred tax assets (included in prepaid expense and other current assets)	65.4	80.0
Deferred tax liabilities	223.4	269.8
Net deferred tax liabilities	158.0	189.8
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Computed expected tax expense on income before taxes at federal statutory rate	127.3	101.4	84.4
Increase (Decrease) Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
State and local income taxes net of federal income tax benefit	6.8	4.9	4.8
Foreign tax rate differential	(7.4)	(4.2)	3.6
Manufacturing tax benefits	(7.5)	(5.8)	(4.4)
Other	5.4	0.9	3.9
Actual income tax expense	124.6	97.2	92.3
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Federal statutory rate	35.00%	35.00%	35.00%
Increase (Decrease) Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
State and local income taxes net of federal income tax benefit	1.90%	1.70%	2.00%
Foreign tax rate differential	(2.00%)	(1.40%)	1.50%
Manufacturing tax benefits	(2.10%)	(2.00%)	(1.80%)
Other	1.50%	0.30%	1.60%
Effective tax rate	34.30%	33.60%	38.30%
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	21.4	25.6
Additions based on tax positions related to the current year	2.3	3.6
Additions for tax positions of prior years	3.2	5.1
Reductions for tax positions of prior years	(0.6)	(9.9)
Reductions due to a lapse of the statute of limitations	(1.7)	(2.9)
Settlements	(0.5)	(0.1)
Balance at end of year	24.1	21.4	25.6
Operating loss carryforwards	72.1
Operating loss carryforwards subject to expiration	28.5
Foreign tax credit carryforward	25.0
Valuation allowance	47.9	42.1
Undistributed foreign subsidiaries earnings	203.7
Unrecognized tax benefits that would impact effective tax rate	24.1	21.4
Interest and penalties	6.1	6.5
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	7.0
Continuing Operations [Member]
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
U.S. federal	1.0	13.9	16.9
Foreign	(0.7)	(14.8)	(10.7)
State and local	(0.8)	1.6	2.5
Total deferred tax expense	$ (0.5)	$ 0.7	$ 8.7