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Reclassifications Out of Accumulated Other Comprehensive Income (Loss) (Tables) | 12 Months Ended
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Dec. 31, 2015
Reclassifications Out of Accumulated Other Comprehensive Income (Loss) [Abstract] |
Changes in Accumulated Other Comprehensive Income (Loss) [Table Text Block] | Changes in accumulated other comprehensive loss, net of tax, for the years ended December 31, 2015, 2014 and 2013, were as follows:
| Unrealized Gain (Loss) on Available-for-sale Securities | Defined Benefit Pension, Other Postretirement Items (a) | Gain (Loss) on Cash Flow Hedge | Total
Millions |  |  |  |
Balance as of December 31, 2012 | $(0.1) | $(21.5) | $(0.4) | $(22.0)
Other Comprehensive Income Before Reclassifications | 1.3 |  | 3.2 |  | 0.1 |  | 4.6 |
Amounts Reclassified From Accumulated Other Comprehensive Loss | (1.3 | ) | 1.6 |  | — |  | 0.3 |
Net Other Comprehensive Income | — |  | 4.8 |  | 0.1 |  | 4.9 |
Balance as of December 31, 2013 | (0.1 | ) | (16.7 | ) | (0.3 | ) | (17.1 | )
Other Comprehensive Income (Loss) Before Reclassifications | (0.3 | ) | (5.2 | ) | 0.2 |  | (5.3 | )
Amounts Reclassified From Accumulated Other Comprehensive Loss | 0.1 |  | 1.2 |  | — |  | 1.3 |
Net Other Comprehensive Income (Loss) | (0.2 | ) | (4.0 | ) | 0.2 |  | (4.0 | )
Balance as of December 31, 2014 | (0.3 | ) | (20.7 | ) | (0.1 | ) | (21.1 | )
Other Comprehensive Income (Loss) Before Reclassifications | (0.4 | ) | (4.3 | ) | 0.1 |  | (4.6 | )
Amounts Reclassified From Accumulated Other Comprehensive Loss | (0.1 | ) | 1.3 |  | — |  | 1.2 |
Net Other Comprehensive Income (Loss) | (0.5 | ) | (3.0 | ) | 0.1 |  | (3.4 | )
Balance as of December 31, 2015 | $(0.8) | $(23.7) | — |  | $(24.5)
(a) | Defined benefit pension and other postretirement items excluded from our Regulated Operations are recognized in accumulated other comprehensive loss and are subsequently reclassified out of accumulated other comprehensive loss as components of net periodic pension and other postretirement benefit expense. (See Note 17. Pension and Other Postretirement Benefit Plans.)

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- Definition Reclassifications Out of Accumulated Other Comprehensive Income (Loss) [Abstract] + References No definition available. + Details
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- Definition Tabular disclosure of the components of accumulated other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580 + Details
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