Net Loss Per Share and Shareholders' Equity - Reconciliation of Numerator and Denominator of the Basic and Diluted Net Loss Per Share (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
Numerator:
Net earnings from continuing operations	$ 26.1	$ 14.9	$ 29.4	$ 35.7
Net earnings from continuing operations	$ 4.3	$ 13.8	$ 18.5	$ 36.2
Denominator:
Denominator for basic EPS–weighted-average common shares (in shares)	70,352,461	69,968,794	70,161,998	69,612,986
Dilutive effect of stock-based compensation arrangements (in shares)	1,583,590	2,023,495	1,315,756	2,180,790
Denominator for diluted EPS–adjusted weighted-average common shares (in shares)	71,936,051	71,992,289	71,477,754	71,793,776
Basic EPS (in dollars per share)	$ 0.37	$ 0.22	$ 0.42	$ 0.51
Diluted EPS (in dollars per share)	$ 0.36	$ 0.21	$ 0.41	$ 0.49