CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) Parenthetical - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Pension Plan and Restoration of Retirement Income Plan:
Amortization of deferred net loss	$ 0.2	$ 0.2
Postretirement Benefit Plans:
Amortization of prior service cost	(0.1)	(0.1)
Pension Plans [Member]
Other Comprehensive Income (Loss), Defined Benefit Plan, Adjustment for Settlement or Curtailment Gain (Loss), Tax	$ 2.2	$ 0.0

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

No definition available.

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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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Data Type:	xbrli:monetaryItemType
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- References

No definition available.

+ Details

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683

+ Details

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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

+ Details

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