INVESTMENT IN ATC - ATC INCOME STATEMENT AND BALANCE SHEET (Details) (ATC, USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
ATC
Income statement data
Revenues	$ 152.4	$ 163.3
Operating expenses	80.0	78.6
Other expense	24.4	21.6
Net income	48.0	63.1
Balance sheet data
Current assets	69.4		66.4
Noncurrent assets	3,779.3		3,728.7
Total assets	3,848.7		3,795.1
Current liabilities	325.7		313.1
Long-term debt	1,701.0		1,701.0
Other noncurrent liabilities	188.9		163.8
Shareholders' equity	1,633.1		1,617.2
Total liabilities and shareholders' equity	$ 3,848.7		$ 3,795.1

The amount of long-term debt reported by an equity method investment of the entity.

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The amount of other expenses reported by an equity method investment of the entity, which are not separately shown.

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No definition available.

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The amount of other noncurrent liabilities reported by an equity method investment of the entity.

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No definition available.

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The amount of assets reported by an equity method investment of the entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

The amount of the cost of sales reported by an equity method investment of the entity.

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No definition available.

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- Definition

The amount of current assets reported by an equity method investment of the entity.

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The amount of current liabilities reported by an equity method investment of the entity.

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Amount of equity, excluding noncontrolling interest, attributable to the equity method investment of the entity.

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The amount of liabilities and equity reported by an equity method investment of the entity.

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The amount of net income (loss) reported by an equity method investment of the entity.

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The amount of noncurrent assets reported by an equity method investment of the entity.

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- Definition

The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

+ References

No definition available.

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