v2.4.0.8

Pension And Other Postretirement Benefits (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 6 Months Ended |  | 3 Months Ended | 6 Months Ended |  | 3 Months Ended | 6 Months Ended
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Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 | May 31, 2013 | Jun. 30, 2013 Pension Plan [Member] | Mar. 31, 2013 Pension Plan [Member] | Jun. 30, 2012 Pension Plan [Member] | Jun. 30, 2013 Pension Plan [Member] | Jun. 30, 2012 Pension Plan [Member] | Feb. 28, 2013 Pension Plan [Member] | Jun. 30, 2013 Other Postretirement Benefits [Member] | Jun. 30, 2012 Other Postretirement Benefits [Member] | Jun. 30, 2013 Other Postretirement Benefits [Member] | Jun. 30, 2012 Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pension and other postretirement benefit cost capitalized | $ 2.3 | $ 5.3 | $ 25.8 | $ 10.9 |  |  |  |  |  |  |  |  |  |  |
Employer contributions |  |  |  |  |  |  |  |  | 7.2 |  |  |  |  | 20.2 |
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements |  |  |  |  |  | 3.6 | 20.7 | 0 | 24.3 | 0 |  | 0 | 0 | 0 | 0
Change in Pension Projected Benefit Obligation, net of plan assets, due to Interim Measurement |  |  |  |  | 30.7 |  |  |  |  |  | 18.6 |  |  |  |
Change in regulatory assets due to Interim Measurement |  |  |  |  | 30.8 |  |  |  |  |  | 36.1 |  |  |  |
Change in Accumulated Other Comprehensive Income due to Interim Measurement |  |  |  |  | 3.5 |  |  |  |  |  | 3.2 |  |  |  |
Change in Net Periodic Benefit Cost due to Interim Measurement |  |  |  |  |  |  |  |  | $ 4.6 |  |  |  |  |  |

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- Definition Change in Accumulated Other Comprehensive Income due to Interim Measurement - associated with the August 31, 2011 pension plan settlement. + References No definition available. + Details
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- Definition Change in Net Periodic Benefit Cost due to Interim Measurement - associated with August 31, 2012 pension plan settlement + References No definition available. + Details
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- Definition Change in Pension Projected Benefit Obligation, net of plan assets, due to Interim Measurement - associated with August 31, 2012 pension plan settlement + References No definition available. + Details
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- Definition Change in regulatory assets due to Interim Measurement - associated with August 31, 2012 pension plan settlement + References No definition available. + Details
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- Definition Pension and other postretirement benefit cost capitalized + References No definition available. + Details
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- Definition The increase in the fair value of plan assets from contributions made by the employer. + 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 (b)(3) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 15 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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