Stock Compensation - Stock Options - Narrative (Details) - Stock Options - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	$ 0.4	$ 0.3	$ 2.1
Unrecognized compensation cost related to stock options	$ 1.0
Weighted average period	3 years 4 months 24 days

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

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Amount of cost to be recognized for option 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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