Goodwill and Other Intangible Assets

3 Months Ended

Mar. 31, 2024

Goodwill and Other Intangible Assets [Abstract]

Goodwill and Other Intangible Assets

Note 7.  Goodwill and Other Intangible Assets

Goodwill and other intangible assets with indefinite lives are not amortized, but instead are assessed for impairment, at least annually. The carrying amount of goodwill was $913.1 million and $913.6 million as of March 31, 2024 and December 31, 2023, respectively.  The net change in goodwill from December 31, 2023 to March 31, 2024 is attributable to the effects of foreign exchange.

Acquired intangible assets subject to amortization as of March 31, 2024 and December 31, 2023 were as follows:

			Mar. 31, 2024				Dec. 31, 2023
(in millions of dollars)	Weighted Average Useful Life (Years)		Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Tradenames		34	$	221.3	$	60.3	$	221.5	$	59.1
Technology		13		18.8		14.6		18.8		14.2
Patents and trademarks		19		6.4		6.4		6.4		6.4
Customer relationships		21		78.4		16.0		79.0		15.0
		29	$	324.9	$	97.3	$	325.7	$	94.7

The weighted average amortization period for acquired intangible assets subject to amortization is approximately 29 years.  Estimated amortization expense is $8.8 million for the remainder of 2024, $47.8 million for 2025–2028 and $171.0 million thereafter.