Commitments and Contingencies, Textuals (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
Environmental accrual	$ 21.7
Expenditures to be charged to environmental accruals, 2012	1.0
Expenditures to be charged to environmental accruals, 2013	3.6
Expenditures to be charged to environmental accruals, 2014	1.8
Expenditures to be charged to environmental accruals, 2015	0.8
Expenditures to be charged to environmental accruals, 2016	0.6
Expenditures to be charged to environmental accruals, thereafter	13.9
Potential increase in environmental costs	$ 18.7
Expected period related to remediation expenditures for environmental contingencies	30 years
Expected period related to excess environmental costs over current accruals	30 years
Time period within which Companys recorded estimate of its obligation may change	12 months

Expected period related to excess environmental expenditures over current accruals

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- Definition

Expected Period Related to Remediation Expenditures for Environmental Contingencies.

+ References

No definition available.

+ Details

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- Definition

Potential additional environmental costs.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 25

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 96-1

-Paragraph 161

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section Y

-Paragraph Question 1

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.Y.Q1)

-URI http://asc.fasb.org/extlink&oid=6572457&loc=d3e149879-122751

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- Definition

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.

+ References

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- Definition

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.

+ References

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- Definition

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.

+ References

+ Details

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- Definition

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.

+ References

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- Definition

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.

+ References

+ Details

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