Pension and Postretirement Plans - Narrative (Details)	6 Months Ended
	Jun. 30, 2022 USD ($) Plan	Jun. 30, 2021 USD ($)
Cincinnati Plans [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Number of noncontributory defined benefit pension plans | Plan	3
Pension Plans, Defined Benefit [Member] | Qualified Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Contributions to pension plans	$ 0	$ 800,000
Expected future employer contributions, next fiscal year	0
Pension Plans, Defined Benefit [Member] | Nonqualified Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Contributions to pension plans	1,000,000.0	1,200,000
Expected future employer contributions, next fiscal year	3,000,000
Pension Plans, Defined Benefit [Member] | Hawaii Plans [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Decrease in benefit obligations	5,400,000	6,700,000
Settlements	5,400,000	6,700,000
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Expected future employer contributions, next fiscal year	7,000,000
Contributions to postretirement plans	$ 3,200,000	$ 3,100,000