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Stock Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 4.8	$ 3.5	$ 9.5	$ 13.1
Tax benefit from share-based compensation	0.7	$ 0.3	$ 2.0	$ 2.4
Weighted-average remaining contractual term, outstanding options			4 years 3 months 10 days
Weighted-average remaining contractual term, exercisable options			3 years 8 months 12 days
Outstanding options, intrinsic value	5.8		$ 5.8
Exercisable options, intrinsic value	$ 5.3		$ 5.3
Share price (in usd per share)	$ 38.07		$ 38.07
Unrecognized compensation costs, options	$ 0.7		$ 0.7
Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for plan (in shares)	2,270,795		2,270,795
2019 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for plan (in shares)	1,914,083		1,914,083
PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding (in shares)	0		0
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding (in shares)	1,494,326		1,494,326		406,575
Unrecognized compensation costs	$ 45.8		$ 45.8
Unrecognized compensation cost, recognition period			2 years 4 months 24 days
Restricted Stock Awards (RSAs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding (in shares)	929,096		929,096		2,289,446
Unrecognized compensation costs	$ 22.5		$ 22.5
Unrecognized compensation cost, recognition period			2 years 6 months
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, recognition period			1 year 10 months 17 days