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Employee Benefits Schedule of Allocation of Plan Assets (Details) | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011
Actual [Member] | Pension Plans, Defined Benefit [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity Securities | 68.00% | 68.00%
Debt Securities | 32.00% | 32.00%
defined benefit pension plan asset allocation | 100.00% | 100.00%
Actual [Member] | Other Postretirement Benefit Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity Securities | 63.00% | 61.00%
Debt Securities | 37.00% | 39.00%
defined benefit pension plan asset allocation | 100.00% | 100.00%
Actual [Member] | Non Qualified Benefit Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity Securities | 17.00% | 30.00%
Debt Securities | 6.00% | 7.00%
defined benefit pension plan asset allocation | 100.00% | 100.00%
Insurance contracts | 77.00% | 63.00%
Target [Member] | Pension Plans, Defined Benefit [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity Securities | 67.00% | 67.00%
Debt Securities | 33.00% | 33.00%
defined benefit pension plan asset allocation | 100.00% | 100.00%
Target [Member] | Other Postretirement Benefit Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity Securities | 72.00% | 72.00%
Debt Securities | 28.00% | 28.00%
defined benefit pension plan asset allocation | 100.00% | 100.00%
Target [Member] | Non Qualified Benefit Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Equity Securities | 17.00% | 23.00%
Debt Securities | 10.00% | 14.00%
defined benefit pension plan asset allocation | 100.00% | 100.00%
Insurance contracts | 73.00% | 63.00%

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- Definition defined benefit pension plan asset allocation total + References No definition available. + Details
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- Definition Portion of Non-qualified benefit plans assets invested in insurance contracts. + References No definition available. + Details
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- Definition Target allocation 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 + 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. + Details
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