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Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted			89,225
Income tax benefit	$ 0.2	$ 0.2	$ 0.4	$ 0.5
Treasury Stock, Shares, Acquired			255,000
Treasury Stock Acquired, Average Cost Per Share			$ 38.04
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	0.6	0.9	$ 1.4	1.8
Share-based Payment Arrangement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	0.7	1.0	1.6	2.0
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	0.1	0.1	0.2	0.2
Total Shareholder Return [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	0.6	0.7	1.3	1.5
Performance Units Related to Earnings Per Share [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 0.0	$ 0.2	$ 0.1	$ 0.3