Pension and Postretirement Plans (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Jul. 02, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Defined Benefit Plan Disclosure [Line Items]
Capitalized portion of defined benefit contribution percent			13.00%		13.00%
Amortization of:
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year	7.00%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	5.00%
Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate	2026
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Payment for Pension and Other Postretirement Benefits				$ 11.0
Amortization of:
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.14%
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Payment for Pension and Other Postretirement Benefits				6.2
Amortization of:
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.22%
Cincinnati Plans [Member] | Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost		$ 0.0	$ 0.0	0.0	$ 0.0
Other components of pension and postretirement benefit plans expense:
Interest cost on projected benefit obligation		4.2	4.9	12.5	14.6
Expected return on plan assets		(6.2)	(6.5)	(18.6)	(19.5)
Amortization of:
Prior service benefit		0.0	0.0	0.0	0.0
Actuarial loss		4.2	4.3	12.7	13.1
Total amortization		4.2	4.3	12.7	13.1
Pension / postretirement costs		2.2	2.7	6.6	8.2
Cincinnati Plans [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year		9.0		9.0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost		0.1	0.1	0.2	0.2
Other components of pension and postretirement benefit plans expense:
Interest cost on projected benefit obligation		0.8	0.8	2.4	2.4
Expected return on plan assets		0.0	0.0	0.0	0.0
Amortization of:
Prior service benefit		(0.7)	(1.2)	(2.3)	(3.4)
Actuarial loss		1.0	1.2	3.1	3.5
Total amortization		0.3	0.0	0.8	0.1
Pension / postretirement costs		1.2	$ 0.9	3.4	$ 2.7
Cincinnati Plans [Member] | Qualified Plan [Member] | Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year		4.0		4.0
Cincinnati Plans [Member] | Nonqualified Plan [Member] | Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year		3.0		3.0
Hawaii Plans [Member] | Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Payment for Pension and Other Postretirement Benefits				5.0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost		0.0
Other components of pension and postretirement benefit plans expense:
Interest cost on projected benefit obligation		1.7
Expected return on plan assets		(2.5)
Amortization of:
Pension / postretirement costs		(0.8)
Hawaii Plans [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year		0.8		0.8
Payment for Pension and Other Postretirement Benefits				0.4
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost		0.2
Other components of pension and postretirement benefit plans expense:
Interest cost on projected benefit obligation		0.5
Expected return on plan assets		0.0
Amortization of:
Pension / postretirement costs		0.7
Hawaii Plans [Member] | Qualified Plan [Member] | Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year		$ 5.0		$ 5.0