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Stock-Based Compensation and Other Incentive Plans (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 22.0	$ 17.5	$ 10.4
Unrecognized share-based compensation expense	$ 19.2
Weighted-average period for recognition of unrecognized share-based compensation expense	3 years
Time Based Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Time Based Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance Based Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Volatility rate	36.00%
2016 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for incentive plan (in shares)	3.0
Number of shares available for grant (in shares)	2.3
Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period	3 years
Compensation expense	$ 1.0	2.7	$ 0.7
Amounts unpaid under long term incentive plan	$ 3.0	$ 6.9