Consolidated Statements of Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital (Deficit)	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Beginning balance at Dec. 31, 2016					$ (43.4)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive loss	$ 6.8
Ending balance at Mar. 31, 2017					(36.6)
Beginning balance at Dec. 31, 2016					(43.4)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	35.1
Other comprehensive loss	11.6
Ending balance at Jun. 30, 2017					(31.8)
Beginning balance at Mar. 31, 2017					(36.6)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	30.1
Other comprehensive loss	4.8
Ending balance at Jun. 30, 2017					(31.8)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting standards adoption (Note 2)	$ 1.1			$ 1.1
Common stock outstanding beginning of period (in shares) at Dec. 31, 2017	139,440,470	139,491,860
Beginning balance at Dec. 31, 2017	$ 110.4	$ 1.4	$ (63.3)	204.5	(32.0)	$ (0.2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive loss	$ 2.6
Ending balance at Mar. 31, 2018					(29.4)
Common stock outstanding beginning of period (in shares) at Dec. 31, 2017	139,440,470	139,491,860
Beginning balance at Dec. 31, 2017	$ 110.4	$ 1.4	(63.3)	204.5	(32.0)	(0.2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	24.6			24.6
Issuance of common stock, stock-based compensation plans (in shares)		605,266
Issuance of common stock, stock-based compensation plans	4.8		4.8
Stock-based compensation expense	5.6		5.6
Other comprehensive loss	(5.7)				(5.7)
Ending balance at Jun. 30, 2018	$ 140.8	$ 1.4	(52.9)	230.2	(37.7)	(0.2)
Common stock outstanding end of period (in shares) at Jun. 30, 2018	140,097,126	140,097,126
Beginning balance at Mar. 31, 2018					(29.4)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	$ 12.1
Other comprehensive loss	(8.3)
Ending balance at Jun. 30, 2018	$ 140.8	$ 1.4	$ (52.9)	$ 230.2	$ (37.7)	$ (0.2)
Common stock outstanding end of period (in shares) at Jun. 30, 2018	140,097,126	140,097,126