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Share-Based Compensation (Narrative) (Details) - USD ($) shares in Thousands, $ in Millions		3 Months Ended		6 Months Ended
	May 11, 2017	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	May 05, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units				686
Share-based compensation expense		$ 1.8	$ 2.2	$ 2.6	$ 2.4
Employees and Directors [Member] | 2017 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares available for grant	3,300					1,500
Employees and Directors [Member] | 2007 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Underlying equity awards issued	1,700

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

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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