Stock-Based Compensation - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares were available for grant under two plans (in shares)	1,400,000
Shares surrendered to the Company (in shares)	17,699
Numbers of shares surrendered (in shares)	1,482
Stock-based employee compensation	$ 3.8	$ 3.4
Unrecognized compensation cost	$ 10.4
Remaining vesting period over which cost expected to be recognized	3 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options exercised	$ 2.0	6.9
Tax benefit for impact of share based compensation	$ 0.4	1.0
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock grant (in shares)	10,450
Restricted Stock \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based employee compensation	$ 0.4	$ 0.3
Restricted stock grant (in shares)	7,950	4,257

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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