Commitments and Contingencies, Textuals (Details) (USD $) In Millions	Sep. 30, 2011
Commitments and Contingencies Disclosure [Abstract]
Minimum rental commitments under operating lease, 2011	$ 7.8
Minimum rental commitments under operating lease, 2012	7.4
Minimum rental commitments under operating lease, 2013	6.4
Minimum rental commitments under operating lease, 2014	3.6
Minimum rental commitments under operating lease, 2015	2.9
Minimum rental commitments under operating lease, thereafter	35.2
Potential increase in environmental costs	21.9
Environmental accrual	21.4
Expenditures to be charged to environmental accruals, 2011	0.4
Expenditures to be charged to environmental accruals, 2012	1.2
Expenditures to be charged to environmental accruals, 2013	3.6
Expenditures to be charged to environmental accruals, 2014	0.8
Expenditures to be charged to environmental accruals, 2015	0.9
Expenditures to be charged to environmental accruals, after 2015	$ 14.5
Expected Period Related To Remediation Expenditures For Environmental Contingencies	30 years
Expected period related to excess environmental expenditures over current accruals	30 years
Time period within which Company's recorded estimate of its obligation may change	12 months

Expected period related to excess environmental expenditures over current accruals

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Expected Period Related to Remediation Expenditures for Environmental Contingencies.

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Potential additional environmental costs.

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Time period within which Company's recorded estimate of its obligation may change.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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The portion of the estimated aggregate undiscounted amount of the accrual for environmental loss contingencies that is expected to be paid after the fifth year after the balance sheet date.

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The portion of the estimated aggregate undiscounted amount of the accrual for environmental loss contingencies that is expected to be paid in the fifth year after the balance sheet date.

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The portion of the estimated aggregate undiscounted amount of the accrual for environmental loss contingencies that is expected to be paid in the fourth year after the balance sheet date.

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The portion of the estimated aggregate undiscounted amount of the accrual for environmental loss contingencies that is expected to be paid in the second year after the balance sheet date.

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The portion of the estimated aggregate undiscounted amount of the accrual for environmental loss contingencies that is expected to be paid in the third year after the balance sheet date.

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The portion of the estimated aggregate undiscounted amount of the accrual for environmental loss contingencies that is expected to be paid within one year of the balance sheet date.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within one year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fifth year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fourth year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the third year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the second year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due after the fifth year from the balance sheet date on leases defined as operating.

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