Goodwill and Other Intangible Assets

12 Months Ended

Dec. 31, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

The changes in the net carrying amount of goodwill for the years ended December 31, 2020 and 2019, respectively, are as follows (in millions):


Balance as of January 1, 2019	$	8,171
Goodwill related to current year acquisitions	34
Goodwill related to disposals	(11)
Goodwill related to prior year acquisitions	2
Foreign currency translation	(31)
Balance as of December 31, 2019	$	8,165
Goodwill related to current year acquisitions	314
Goodwill related to disposals	(3)

Foreign currency translation	190
Balance as of December 31, 2020	$	8,666

Other intangible assets by asset class are as follows (in millions):


	As of December 31
	2020						2019
	Gross Carrying Amount		Accumulated Amortization and Impairment		Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization and Impairment		Net Carrying Amount
Customer-related and contract-based	$	2,337	$	1,775	$	562	$	2,264	$	1,600	$	664
Tradenames (1)	14		13		1		1,029		956		73
Technology and other	435		358		77		380		334		46
Total	$	2,786	$	2,146	$	640	$	3,673	$	2,890	$	783

(1)In 2020, Aon wrote off $1.0 billion of fully amortized tradenames, including the Hewitt and Benfield tradenames. The company no longer expects to receive economic benefits from these tradenames.

Amortization expense and impairment charges from finite lived intangible assets were $246 million, $392 million, and $593 million for the years ended December 31, 2020, 2019, and 2018, respectively.

The estimated future amortization for finite-lived intangible assets as of December 31, 2020 is as follows (in millions):


	Estimated Future Amortization
For the years ended
2021	$	144
2022	102
2023	91
2024	73
2025	59
Thereafter	171
Total	$	640