Employee Benefit Plans (Allocation of Plan Assets) (Details)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Pension Plans
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation, Equity securities	41.00%
Target allocation, Debt securities	38.00%
Target allocation, Other	21.00%
Target Allocation, Total	100.00%
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]
Actual allocation, Equity securities	39.00%	43.00%
Actual allocation, Debt securities	40.00%	33.00%
Actual allocation, Other	21.00%	24.00%
Actual Allocation, Total	100.00%	100.00%
Postretirement Benefit Plans
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation, Equity securities	60.00%
Target allocation, Debt securities	40.00%
Target allocation, Other	0.00%
Target Allocation, Total	100.00%
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]
Actual allocation, Equity securities	60.00%	60.00%
Actual allocation, Debt securities	40.00%	40.00%
Actual allocation, Other	0.00%	0.00%
Actual Allocation, Total	100.00%	100.00%

Defined Benefit Plan, Target Plan Asset Allocation

No definition available.

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- Details

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- Definition

The percentage of the fair value of debt securities to the fair value of total plan assets held as of the measurement date.

+ 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(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

-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)(1)

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

+ Details

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- Definition

The percentage of the fair value of equity securities to the fair value of total plan assets held as of the measurement date.

+ References

+ Details

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- Definition

The percentage of the fair value of investments other than debt securities, equity securities, and real estate to the fair value of total plan assets held as of the measurement date.

+ References

+ Details

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- 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

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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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- Definition

Target allocation percentage in other than debt securities, equity securities, and real estate 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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- Definition

The aggregate percentage of the fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of total plan assets held as of the measurement date.

+ References

+ Details

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