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Share Based Compensation - Plans (Details) - USD ($) $ in Millions			3 Months Ended	12 Months Ended
	May 17, 2019	May 19, 2017	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation
Issued (in shares)				700,000
Forfeited (in shares)				200,000
Available for issuance (in shares)				1,700,000
Stock-based compensation expense				$ 18.4	$ 13.4	$ 13.1
Special Equity Plan
Share Based Compensation
Shares of common stock authorized for issuance under the share-based compensation plan		1,500,000
2019 Omnibus Incentive Plan
Share Based Compensation
Shares of common stock authorized for issuance under the share-based compensation plan	2,025,000			2,000,000.0
2016 Omnibus Incentive Plan
Share Based Compensation
Shares of common stock authorized for issuance under the share-based compensation plan				200,000
Additional shares authorized (in shares)	243,611
Stock Options \| Special Equity Plan
Share Based Compensation
Issued (in shares)		800,000
Performance-based stock awards \| Special Equity Plan
Share Based Compensation
Issued (in shares)		300,000
Stock-based compensation expense			$ 5.9