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Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	May 03, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved under plan					4,500,000
Recognized stock-based compensation expense	$ 1.6	$ 0.3	$ 7.1	$ 5.9
Unearned compensation cost related to the unvested portion of all stock-based awards	$ 9.9		$ 9.9
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share based compensation units granted			300,000
Weighted-average grant-date fair value			$ 5.28
Performance Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share based compensation units granted			200,000
Weighted-average grant-date fair value			$ 14.64
Deferred Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share based compensation units granted			200,000
Weighted average grant date fair value	$ 14.64		$ 14.64
Vesting period			3 years