IAA Separation and Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Discontinued Operations
Cash distribution received from IAA			$ 1,278.0
Professional fees associated with spin-off		$ 0.8
Discontinued Operations - Results of Operations
Operating revenues	$ 0.0	357.2
Cost of services (exclusive of depreciation and amortization)	0.0	218.4
Selling, general and administrative	0.0	32.4
Depreciation and amortization	0.0	21.8
Total operating expenses	0.0	272.6
Operating profit	0.0	84.6
Interest expense	0.0	0.3
Other expense, net	0.0	0.1
Income from discontinued operations before income taxes	0.0	84.2
Income taxes	0.0	21.7
Income from discontinued operations	$ 0.0	$ 62.5

Professional fees associated with discontinued operations.

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