Investment in American Transmission Company - Changes to Investment (Details) - USD ($) $ in Millions |
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2016 |
Mar. 31, 2015 |
Jun. 29, 2015 |
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| Changes to investment in ATC | |||
| Investment in ATC, balance at beginning of period | $ 1,380.9 | ||
| Add: Earnings from equity method investment | 38.5 | $ 16.1 | |
| Add: Adjustment to equity method goodwill | (24.4) | ||
| Investment in ATC, balance at end of period | $ 1,422.5 | ||
| ATC | |||
| Investment in ATC | |||
| Ownership interest in ATC (as a percent) | 60.00% | 26.20% | |
| Changes to investment in ATC | |||
| Investment in ATC, balance at beginning of period | $ 1,380.9 | 424.1 | |
| Add: Earnings from equity method investment | 38.5 | 16.1 | |
| Add: Capital contributions | 9.0 | 1.3 | |
| Add: Adjustment to equity method goodwill | 9.3 | 0.0 | |
| Less: Distributions received | 15.1 | 10.4 | |
| Less: Other | 0.1 | 0.0 | |
| Investment in ATC, balance at end of period | $ 1,422.5 | $ 431.1 | |
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- Definition This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Cash or noncash contributions of capital made by the entity to an equity method investee. No definition available.
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- Definition Other items not separately disclosed that impact investments accounted for under the equity method of accounting. No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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