Benefit Plans - Allocation of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Allocation range	100.00%	100.00%
Fair value of plan assets	$ 32.3	$ 29.4
Pension plan assets in the fair value hierarchy
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	32.3	29.4
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.6	0.7
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	31.7	28.7
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Pension plan assets measured at NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0.0	$ 0.0
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Allocation range	16.00%	28.00%
Equity securities \| United States
Defined Benefit Plan Disclosure [Line Items]
Target allocation	19.00%
Equity securities \| Pension plan assets in the fair value hierarchy
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 5.3	$ 8.2
Equity securities \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Equity securities \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5.3	8.2
Equity securities \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0.0	$ 0.0
Debt securities
Defined Benefit Plan Disclosure [Line Items]
Allocation range	80.00%	68.00%
Debt securities \| United States
Defined Benefit Plan Disclosure [Line Items]
Target allocation	79.00%
Other
Defined Benefit Plan Disclosure [Line Items]
Allocation range	4.00%	4.00%
Other \| United States
Defined Benefit Plan Disclosure [Line Items]
Target allocation	2.00%
Cash \| Pension plan assets in the fair value hierarchy
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0.6	$ 0.7
Cash \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.6	0.7
Cash \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Cash \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
International mutual funds \| Pension plan assets in the fair value hierarchy
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	25.9	20.4
International mutual funds \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
International mutual funds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	25.9	20.4
International mutual funds \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Other mutual funds \| Pension plan assets in the fair value hierarchy
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.5	0.1
Other mutual funds \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Other mutual funds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.5	0.1
Other mutual funds \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0.0	$ 0.0
Minimum \| Equity securities \| United States
Defined Benefit Plan Disclosure [Line Items]
Allocation range	15.00%
Minimum \| Debt securities \| United States
Defined Benefit Plan Disclosure [Line Items]
Allocation range	75.00%
Minimum \| Other \| United States
Defined Benefit Plan Disclosure [Line Items]
Allocation range	2.00%
Maximum \| Equity securities \| United States
Defined Benefit Plan Disclosure [Line Items]
Allocation range	20.00%
Maximum \| Debt securities \| United States
Defined Benefit Plan Disclosure [Line Items]
Allocation range	85.00%
Maximum \| Other \| United States
Defined Benefit Plan Disclosure [Line Items]
Allocation range	5.00%

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

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