Discontinued Operations - Schedule of Amounts Included in Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net earnings from discontinued operations	$ 29.7	$ 27.4	$ 82.1	$ 93.4
Held-for-sale or Disposed of by Sale | TransCore Holdings Inc, Zetec and Civco Radiotherapy
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net revenues	158.6	167.9	472.1	503.2
Cost of sales	91.3	101.9	280.2	296.7
Gross profit	67.3	66.0	191.9	206.5
Selling, general and administrative expenses(1)	25.6	28.9	87.8	86.6
Income from operations	41.7	37.1	104.1	119.9
Other income (expense), net	0.2	(0.2)	1.4	0.2
Earnings before income taxes	41.9	36.9	105.5	120.1
Income taxes	12.2	9.5	23.4	26.7
Net earnings from discontinued operations	29.7	27.4	82.1	93.4
Stock-based compensation expense	$ 1.4	$ 1.2	$ 3.2	$ 3.5