Stock-Based Compensation Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense associated with stock-based compensation	$ 2.0	$ 2.0
Compensation cost related to unvested awards, not yet recognized	$ 18.0
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period	239,617
Weighted Average Grant Date Fair Value, Other than options	$ 31.75
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period	250,178
Additional Paid-in Capital [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense associated with stock-based compensation	$ 2.0	$ 2.0

Amount of increase to additional paid-in capital (APIC) for recognition of cost for award under share-based payment arrangement.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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