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-Publisher FASB
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Share Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Share Based Compensation (Details) - USD ($) $ in Millions	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Stock based compensation plans
Share-based Payment Arrangement, Noncash Expense	$ 4.3	$ 3.7	$ 5.9	$ 5.5
Employee Service Share-based Compensation Not yet Recognized	$ 11.9		$ 11.9
Employees [Member] \| Restricted Stock [Member]
Stock based compensation plans
Grants of restricted shares (in shares)			185,820
Shares withheld for tax withholding obligation			53,609
Employees, Non-Directors [Member] \| Restricted Stock [Member]
Stock based compensation plans
Grants of restricted shares (in shares)			37,416