Goodwill and Other Identifiable Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2018

The changes in the carrying amount of goodwill for the years ended December 31, 2018 and 2017 by reportable segment were as follows:



In millions	December 31, 2017		Foreign currency translation/other			December 31, 2018
Aquatic Systems	$	973.1	$	(7.2	)	$	965.9
Filtration Solutions	667.6		(24.1		)	643.5
Flow Technologies	472.1		(8.8		)	463.3
Total goodwill	$	2,112.8	$	(40.1	)	$	2,072.7



In millions	December 31, 2016		Acquisitions/ divestitures		Foreign currency translation/other		December 31, 2017
Aquatic Systems	$	918.7	$	—	$	54.4	$	973.1
Filtration Solutions	630.2		27.3		10.1		667.6
Flow Technologies	445.7		—		26.4		472.1
Total goodwill	$	1,994.6	$	27.3	$	90.9	$	2,112.8

Identifiable intangible assets consisted of the following at December 31:



	2018							2017
In millions	Cost		Accumulated amortization			Net		Cost		Accumulated amortization			Net
Definite-life intangibles
Customer relationships	$	347.1	$	(247.9	)	$	99.2	$	360.9	$	(229.9	)	$	131.0
Trade names	0.4		(0.4		)	—		1.5		(1.4		)	0.1
Proprietary technology and patents	86.2		(68.4		)	17.8		117.0		(89.3		)	27.7
Total finite-life intangibles	433.7		(316.7		)	117.0		479.4		(320.6		)	158.8
Indefinite-life intangibles
Trade names	159.3		—			159.3		163.0		—			163.0
Total intangibles	$	593.0	$	(316.7	)	$	276.3	$	642.4	$	(320.6	)	$	321.8

Estimated future amortization expense for identifiable intangible assets during the next five years is as follows:



In millions	2019		2020		2021		2022		2023
Estimated amortization expense	$	27.4	$	22.4	$	17.3	$	10.1	$	7.8