CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Document Fiscal Period Focus			Q3
Net earnings (loss)	$ 5.6	$ 25.4	$ (23.0)	$ 28.6
Foreign currency translation	9.2	(4.9)	5.1	(3.4)
Employee benefit plans:
Amortization or settlement of actuarial losses and prior service costs	0.3	0.1	0.5	0.4
Net change in employee benefit plans	0.3	0.1	0.5	0.4
Changes in fair value of cash flow hedges:
Unrealized net gains (losses) arising during period	1.4	(1.3)	0.5	(1.1)
Net (gains) losses reclassified into earnings	(0.5)	0.4	(0.1)	0.5
Total cash flow hedges	0.9	(0.9)	0.4	(0.6)
Other comprehensive earnings (loss), net of tax	10.4	(5.7)	6.0	(3.6)
Other comprehensive loss, net of tax			6.0	(3.6)
Comprehensive earnings (loss)	16.0	19.7	(17.0)	25.0
Stockholders' Equity Attributable to Parent	1,264.6	1,257.3	1,264.6	1,257.3
Net earnings (loss)	5.6	25.4	(23.0)	28.6
Other comprehensive loss, net of tax			6.0	(3.6)
Stock-based compensation expense	4.8	5.2	12.4	19.2
Common stock issued for exercise of stock options and other	0.1	5.7	1.8	7.5
Tax on restricted stock unit vesting	(0.1)	(0.5)	(6.1)	(6.0)
Treasury Stock, Value, Acquired, Cost Method			(15.0)
Common Stock
Stockholders' Equity Attributable to Parent	0.9	0.9	0.9	0.9
Additional Paid-In Capital
Stockholders' Equity Attributable to Parent	1,582.8	1,566.6	1,582.8	1,566.6
Stock-based compensation expense	4.8	5.2	12.4	19.2
Common stock issued for exercise of stock options and other	0.1	5.7	1.8	7.5
Tax on restricted stock unit vesting	(0.1)	(0.5)	(6.1)	(6.0)
Accumulated Deficit
Statement of Comprehensive Income [Abstract]
Net earnings (loss)	5.6	25.4
Stockholders' Equity Attributable to Parent	(198.1)	(195.6)	(198.1)	(195.6)
Net earnings (loss)	5.6	25.4
Accumulated Other Comprehensive Loss
Changes in fair value of cash flow hedges:
Other comprehensive earnings (loss), net of tax	10.4
Other comprehensive loss, net of tax	10.4	(5.7)	6.0	(3.6)
Stockholders' Equity Attributable to Parent	(106.0)	(114.6)	(106.0)	(114.6)
Other comprehensive loss, net of tax	10.4	$ (5.7)	6.0	$ (3.6)
Treasury Stock
Stockholders' Equity Attributable to Parent	$ (15.0)		(15.0)
Treasury Stock, Value, Acquired, Cost Method			$ (15.0)