Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Common Stock and Stock-Based Compensation Stock-based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 6.1	$ 6.5	$ 6.2	$ 5.9	$ 5.7	$ 5.1	$ 18.8	$ 16.7
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period							10 years
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Granted							635,186
Weighted Average Grant-Date Fair Value per Award							$ 21.63
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period							1 year
Number of Shares Granted							22,937
Weighted Average Grant-Date Fair Value per Award							$ 21.32
Performance units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period							3 years
Number of Shares Granted							284,061
Weighted Average Grant-Date Fair Value per Award							$ 28.47
Minimum \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period							3 years
Maximum \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period							4 years