Goodwill and Other Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

The changes in goodwill by reportable segment are as follows:



(in millions)	Corporate		Small Business		Public		Other⁽¹⁾			Consolidated
Balance at December 31, 2016⁽²⁾	1,074.1		185.9		929.6		265.4			2,455.0
Foreign currency translation	—		—		—		24.6			24.6
Balances as of December 31, 2017⁽²⁾	1,074.1		185.9		929.6		290.0			2,479.6
Foreign currency translation	—		—		—		(16.8		)	(16.8		)
Balances as of December 31, 2018⁽²⁾	$	1,074.1	$	185.9	$	929.6	$	273.2		$	2,462.8


(1)	Other is comprised of CDW UK and Canada reporting units.

(2)

Goodwill is net of accumulated impairment losses of $1,571 million, $354 million and $28 million related to the Corporate, Public and Other segments, respectively.

Schedule of Finite-Lived Intangible Assets

The following table shows estimated useful lives of definite-lived intangible assets:



Classification	Estimated Useful Lives
Customer relationships and contracts	3 to 14 years
Trade name	generally 20 years
Internally developed software	3 to 5 years
Other	1 to 10 years

A summary of intangible assets is as follows:



(in millions)
December 31, 2018	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Customer relationships and contracts	$	2,071.0	$	(1,625.5	)	$	445.5
Trade name	422.1		(237.3		)	184.8
Internally developed software	205.8		(125.4		)	80.4
Other	3.7		(2.2		)	1.5
Total	$	2,702.6	$	(1,990.4	)	$	712.2


December 31, 2017
Customer relationships and contracts	$	2,106.8	$	(1,490.8	)	$	616.0
Trade name	422.2		(216.3		)	205.9
Internally developed software	162.6		(89.6		)	73.0
Other	2.9		(0.8		)	2.1
Total	$	2,694.5	$	(1,797.5	)	$	897.0

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense

Estimated future amortization expense related to intangible assets is as follows:



(in millions)
Years ending December 31,	Estimated Future Amortization Expense
2019	$	215.9
2020	182.2
2021	85.1
2022	37.4
2023	37.4
Thereafter	154.2
Total future amortization expense	$	712.2