Other Intangible Assets

12 Months Ended

Dec. 31, 2023

Goodwill and Intangible Assets Disclosure [Abstract]

Other Intangible Assets

Other Intangible Assets

	December 31, 2023							December 31, 2022
	Weighted Average Remaining Useful Life (Years)	Gross Value		Accumulated Amortization		Net Value		Gross Value		Accumulated Amortization		Net Value
Customer relationships	7.9	$	94.5	$	60.5	$	34.0	$	93.8	$	55.2	$	38.6
Indefinite-lived tradenames	*	25.9		*		25.9		25.7		*		25.7
Technology	11.5	22.8		10.0		12.8		22.4		8.8		13.6
Other	4.1	4.8		4.2		0.6		4.8		4.0		0.8
Total		$	148.0	$	74.7	$	73.3	$	146.7	$	68.0	$	78.7
* Not applicable, as these tradenames have an indefinite life.

Amortization expense of other intangible assets as follows:

	Year Ended December 31,
	2023		2022		2021
Amortization expense	$	6.7	$	6.6	$	6.9

We estimate amortization expense for the five years subsequent to 2023 as follows:

2024	$	6.5
2025	$	6.5
2026	$	6.1
2027	$	6.1
2028	$	5.2