Goodwill

6 Months Ended

Jun. 30, 2023

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill

7. Goodwill

The changes in the carrying amount of goodwill during the six months ended June 30, 2023 (unaudited) were as follows:

(millions)	Commercial		Aviation			Total
Net book value as of December 31, 2022
Goodwill	$	387.0	$	215.7		$	602.7
Accumulated impairment losses		—		(59.5	)		(59.5	)
Total	$	387.0	$	156.2		$	543.2
Foreign currency translation		0.1		0.3			0.4
Net book value as of June 30, 2023
Goodwill	$	387.1	$	216.0		$	603.1
Accumulated impairment losses		—		(59.5	)		(59.5	)
Total	$	387.1	$	156.5		$	543.6