Business and Organization - Revisions to Statements of Operations (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales	$ 365.9	$ 380.4	$ 371.1	$ 328.0	$ 378.2	$ 384.0	$ 368.4	$ 325.5	$ 1,445.4	$ 1,456.1	$ 1,570.1
Cost of sales									908.5	922.3	1,068.4
Gross profit	$ 132.8	$ 143.9	$ 137.2	$ 123.0	$ 139.5	$ 142.0	$ 134.7	$ 117.6	536.9	533.8	501.7
Selling, general and administrative expenses									278.2	291.1	291.6
Loss on early extinguishment of debt									1.7	2.7	0.0
Other expense (income) — net									9.1	9.0	(22.1)
Earnings before income taxes									121.4	102.2	196.4
Income taxes									(11.5)	30.7	40.3
Net earnings									$ 132.9	$ 71.5	$ 156.1
Earnings per share - Basic (in dollars per share)	$ 0.48	$ 0.22	$ 0.20	$ 0.05	$ 0.14	$ 0.17	$ 0.10	$ 0.11	$ 0.96	$ 0.52	$ 1.14
Earnings per share - Diluted (in dollars per share)	0.47	0.22	0.20	0.05	$ 0.14	0.17	0.10	0.11	$ 0.94	$ 0.51	$ 1.14
As Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales					$ 378.7					$ 1,456.6
Cost of sales										923.8
Gross profit					$ 138.5					532.8
Selling, general and administrative expenses										290.1
Loss on early extinguishment of debt									$ 4.4	0.0
Other expense (income) — net									9.0	(9.1)
Earnings before income taxes									118.8	104.8
Income taxes									(15.2)	25.3	$ 39.3
Net earnings									$ 134.0	$ 79.5	$ 157.1
Earnings per share - Basic (in dollars per share)	0.47	0.24	0.22	0.04	$ 0.15	0.18	0.11	0.13	$ 0.96	$ 0.58	$ 1.15
Earnings per share - Diluted (in dollars per share)	0.47	0.24	0.21	0.04	$ 0.15	0.18	0.11	0.13	$ 0.95	$ 0.57	$ 1.15
Computation of Income Tax Expense | Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales					$ (0.5)					$ (0.5)
Cost of sales										(1.5)
Gross profit					$ 1.0					1.0
Selling, general and administrative expenses										1.0
Loss on early extinguishment of debt									$ (2.7)	2.7
Other expense (income) — net									0.1	(0.1)
Earnings before income taxes									2.6	(2.6)
Income taxes									3.7	5.4	$ 1.0
Net earnings									$ (1.1)	$ (8.0)	$ (1.0)
Earnings per share - Basic (in dollars per share)	0.01	(0.02)	(0.02)		$ (0.01)	(0.01)	(0.01)	(0.02)	$ 0.00	$ (0.06)	$ (0.01)
Earnings per share - Diluted (in dollars per share)	$ 0.00	$ (0.02)	$ (0.01)	$ 0.01	$ (0.01)	$ (0.01)	$ (0.01)	$ (0.02)	$ (0.01)	$ (0.06)	$ (0.01)