CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) Parenthetical (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Pension Plan and Restoration of Retirement Income Plan:
Amortization of deferred net loss	$ 0.8	$ 0.3
Postretirement Benefit Plans:
Amortization of deferred net loss	0.2	0.1
Amortization of prior service cost	(0.3)	(0.3)
Amortization of deferred interest rate swap hedging losses	$ 0	$ 0.1

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Tax effect on adjustment out of other comprehensive income for prior service costs recognized as a component of net periodic postretirement benefit cost during the period.

+ References

No definition available.

+ Details

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- Definition

Other Comprehensive Income Reclassification Adjustment On Interest Rate Swaps Included In Net Income, Tax

+ References

No definition available.

+ Details

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- Definition

Other Comprehensive Income Reclassification Of Defined Benefit Postretirement Plans Net Gain Loss Recognized In Net Periodic Benefit Cost Tax

+ References

No definition available.

+ Details

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- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e689-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e640-108580

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