Employee Benefit Plans Investment of Plan Assets (Details) (Pension Plans, Defined Benefit [Member])	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	100.00%	100.00%
Domestic equity securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	41.00%	44.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation range minimum	40.00%
Target allocation range maximum	45.00%
International equity securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	25.00%	20.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation range minimum	20.00%
Target allocation range maximum	30.00%
Domestic fixed income securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	26.00%	28.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation range minimum	25.00%
Target allocation range maximum	30.00%
International fixed income securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	5.00%	5.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation range minimum	4.00%
Target allocation range maximum	6.00%
Real Estate Fund [Member] [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	3.00%	3.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation range minimum	2.00%
Target allocation range maximum	4.00%

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- Definition

Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: 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=21915506&loc=d3e1928-114920

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=21915506&loc=d3e2446-114920

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- Definition

Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

+ Details

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: 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=21915506&loc=d3e2446-114920

Reference 2: 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=21915506&loc=d3e1928-114920

Reference 3: 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.

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