Goodwill and other intangible assets

9 Months Ended

Sep. 30, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Note 12. Goodwill and other intangible assets

A reconciliation of the change in the carrying value of goodwill is as follows (in millions).


	September 30, 2018		December 31, 2017
Balance at beginning of year	$	81,258	$	79,486
Acquisitions of businesses		250		1,545
Other, including foreign currency translation		(181)		227

Balance at end of period	$	81,327	$	81,258

Other intangible assets are summarized as follows (in millions).


	September 30, 2018				December 31, 2017
	Gross carrying amount		Accumulated amortization		Gross carrying amount		Accumulated amortization
Insurance and other	$	40,288	$	8,662	$	40,225	$	7,707
Railroad, utilities and energy		1,026		362		988		324

	$	41,314	$	9,024	$	41,213	$	8,031

Trademarks and trade names	$	5,396	$	744	$	5,381	$	692
Patents and technology		4,408		2,716		4,341		2,493
Customer relationships		28,343		4,351		28,322		3,722
Other		3,167		1,213		3,169		1,124

	$	41,314	$	9,024	$	41,213	$	8,031

Amortization expense in the first nine months was $1,052 million in 2018 and $1,108 million in 2017. Intangible assets with indefinite lives were approximately $18.9 billion as of September 30, 2018 and December 31, 2017.