Goodwill and Acquired Intangibles

12 Months Ended

Dec. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Acquired Intangibles

Goodwill and Acquired Intangibles

Changes in the carrying amount of goodwill by business segment were as follows (in millions):

	Aeronautics		MFC		RMS		Space		Total
Balance at December 31, 2019	$	171	$	2,089	$	6,758	$	1,586	$	10,604
Acquisitions	16		—		—		173		189
Other	—		2		10		1		13
Balance at December 31, 2020	187		2,091		6,768		1,760		10,806
Acquisitions	—		—		—		17		17
Other	—		(1)		(9)		—		(10)
Balance at December 31, 2021	$	187	$	2,090	$	6,759	$	1,777	$	10,813

The gross carrying amounts and accumulated amortization of our acquired intangible assets consisted of the following (in millions):

	2021						2020
	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount
Finite-Lived:
Customer programs	$	3,184	$	(1,431)	$	1,753	$	3,184	$	(1,199)	$	1,985
Customer relationships	120		(96)		24		366		(287)		79
Other	76		(34)		42		85		(24)		61
Total finite-lived intangibles	3,380		(1,561)		1,819		3,635		(1,510)		2,125
Indefinite-Lived:
Trademark	887		—		887		887		—		887
Total acquired intangibles	$	4,267	$	(1,561)	$	2,706	$	4,522	$	(1,510)	$	3,012

Acquired finite-lived intangible assets are amortized to expense primarily on a straight-line basis over the following estimated useful lives: customer programs from nine to 20 years; customer relationships from four to 10 years; and other intangibles assets from three to 10 years.

Amortization expense for acquired finite-lived intangible assets was $285 million, $271 million and $284 million in 2021, 2020 and 2019. Estimated future amortization expense is as follows: $248 million in 2022; $246 million in 2023; $243 million in 2024; $221 million in 2025; and $154 million in 2026.