Pension and Postretirement Plans - Narrative (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) Plan	Jun. 30, 2023 USD ($)
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]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Pension settlement gain	$ (400,000)	$ 0	$ (400,000)	$ 0
Pension Plans, Defined Benefit [Member] | Hawaii Plans [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Settlement	5,500,000
Decrease in benefit obligations	5,500,000
Pension settlement gain	(400,000)
Pension Plans, Defined Benefit [Member] | Qualified Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Contributions to pension plans			0	0
Expected future employer contributions, next fiscal year	1,000,000		1,000,000
Pension Plans, Defined Benefit [Member] | Nonqualified Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Contributions to pension plans			800,000	800,000
Expected future employer contributions, next fiscal year	2,000,000		2,000,000
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Expected future employer contributions, next fiscal year	7,000,000		7,000,000
Contributions to postretirement plans			3,400,000	3,000,000
Pension settlement gain	$ 0	$ 0	$ 0	$ 0