Defined aggregate benefit plan actual allocation percentage of assets.

No definition available.

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- Definition

Defined benefit plan actual allocation percentage of assets cash and cash equivalents.

+ References

No definition available.

+ Details

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- Details

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 35

-Paragraph 50

-URI http://asc.fasb.org/extlink&oid=6867990&loc=d3e12355-114930

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(iv)(b)(i)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 87

-Paragraph 49

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Target allocation percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(2)

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(i)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2446-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(i)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Target allocation maximum percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Target allocation minimum percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

+ Details

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- Definition

Target allocation percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Target allocation maximum percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Target allocation minimum percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

+ Details

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Employee Retirement Plans (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets	$ 290.6	$ 291.1	$ 257.6
Plan assets:
Cash and cash equivalents	3.00%	1.00%
Equity securities	66.00%	68.00%
Equity securities, minimum	55.00%
Equity securities, maximum	65.00%
Debt securities	31.00%	31.00%
Debt securities, minimum	35.00%
Debt securities, maximum	45.00%
Total	100.00%	100.00%
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets	83.2	80.8
Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets	207.4	210.3
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets
Temporary cash investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets	9.7	3.5
Temporary cash investments [Member] \| Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets	9.7	3.5
Common trust funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets	207.4	210.3
Common trust funds [Member] \| Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets	207.4	210.3
Registered investment companies [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets	73.5	71.7
Registered investment companies [Member] \| Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets	73.5	71.7
Corporate stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets		2.9
Corporate stock [Member] \| Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets		2.9
Corporate bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets		2.0
Corporate bonds [Member] \| Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets		2.0
U.S. government obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets		0.7
U.S. government obligations [Member] \| Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated fair value of plan assets		$ 0.7