SIGNIFICANT ACCOUNTING POLICIES (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Intangible asset
Impairment on long lived intangible assets			$ 2.1
Impairments of goodwill	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss
CCF Deposits and Other Long-term Assets
CCF Deposits, Capital Construction Fund Deposits	27.5	0
Other assets and deferred charges	21.8us-gaap_OtherAssetsMiscellaneous	18.3us-gaap_OtherAssetsMiscellaneous
Comprehensive Income (Loss):
Other comprehensive income (loss) net of tax (expense) benefit	(29.8)	22.0	(0.5)
Accumulated other comprehensive loss	(53.3)	(23.5)
Amortization of deferred pension, post-retirement costs and non-qualified plans	$ 52.9	$ 22.6
Customer lists and other \| Minimum
Intangible asset
Expected useful lives	3 years
Customer lists and other \| Maximum
Intangible asset
Expected useful lives	13 years

Represents the amount of amortization of deferred pension, post-retirement costs and non-qualified plans.

No definition available.

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- Definition

The net balance of amount accrued for withdrawal and deposits to the Capital Construction Fund, reflected in the consolidated balance sheets.

+ References

No definition available.

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

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

-Publisher FASB

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-Publisher SEC

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of loss from the write-down 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.

+ References

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

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- Definition

Amount of other miscellaneous assets.

+ References

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- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

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