Goodwill and Other Intangible Assets

9 Months Ended

Sep. 30, 2019

Goodwill And Intangible Assets Disclosure [Abstract]

Goodwill and Other Intangible Assets

Note 6. Goodwill and Other Intangible Assets

The changes in the carrying amount of goodwill by segment for the nine months ended September 30, 2019 were as follows:

	U.S.		International		Total
Net book value as of December 31, 2018	$	438.5	$	11.5	$	450.0
Purchase accounting adjustments		0.1		—		0.1
Foreign exchange and other adjustments		—		0.1		0.1
Net book value as of September 30, 2019	$	438.6	$	11.6	$	450.2

The components of other intangible assets at September 30, 2019 and December 31, 2018 were as follows:

	September 30, 2019							December 31, 2018
	Gross Carrying Amount							Gross Carrying Amount
			Accumulated Amortization			Net Book Value				Accumulated Amortization			Net Book Value
Customer relationships	$	149.1	$	(123.7	)	$	25.4	$	149.3	$	(113.1	)	$	36.2
Trade names		3.9		(3.0	)		0.9		3.9		(2.9	)		1.0
Total other intangible assets	$	153.0	$	(126.7	)	$	26.3	$	153.2	$	(116.0	)	$	37.2

Amortization expense for other intangible assets was $3.6 million and $3.4 million for the three months ended September 30, 2019 and 2018, respectively, and $10.9 million and $10.3 million for the nine months ended September 30, 2019 and 2018, respectively.

The following table outlines the estimated annual amortization expense related to other intangible assets as of September 30, 2019:

For the year ending December 31,	Amount
2019	$	14.6
2020		13.0
2021		0.9
2022		0.9
2023		0.9
2024 and thereafter		6.9
Total	$	37.2