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

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Amount of cash paid to settle liability for award under share-based payment arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Share Based Compensation (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended		9 Months Ended
Share Based Compensation (Details) - USD ($) $ in Millions	Feb. 19, 2021	Jan. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense (benefit)			$ 0.3	$ 0.2	$ 1.6	$ 0.3
2021 Long Term Incentive Plan [Member] \| Performance Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted during period (in units)	10,187
2021 Long Term Incentive Plan [Member] \| Restricted Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted during period (in units)	16,267
2006 Performance Unit Plan and 2013 Director Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash payments distributed related to awards previously granted and now payable		$ 1.9