CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) Parenthetical - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Pension Plan and Restoration of Retirement Income Plan:
Amortization of deferred net loss	$ 0.5	$ 0.4	$ 1.3	$ 1.2
Settlement cost	0.0	0.0	0.0	3.2
Postretirement Benefit Plans:
Amortization of prior service cost	(0.2)	(0.2)	(0.2)	(0.7)
Other Comprehensive Income Reclassification Of Defined Benefit Postretirement Plans Net Gain Loss Recognized In Net Periodic Benefit Cost Tax	$ 4.1	$ 0.0	$ 4.1	$ 0.0

-- None. No documentation exists for this element. --

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- Definition

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 Of Defined Benefit Postretirement Plans Net Gain Loss Recognized In Net Periodic Benefit Cost Tax

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount of tax expense (benefit) for increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4569616-111683

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=84228862&loc=d3e640-108580

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- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

+ References

Reference 1: 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=84228862&loc=d3e640-108580

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