Goodwill and other intangible assets

6 Months Ended

Jun. 30, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and other intangible assets

Note 12. Goodwill and other intangible assets

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

					June 30, 2018		December 31, 2017
Balance at beginning of year					$	81,258	$        79,486
Acquisitions of businesses						177	1,545
Other, including foreign currency translation						(185)	227
Balance at end of period					$	81,250	$        81,258
Other intangible assets are summarized as follows (in millions).
	June 30, 2018				December 31, 2017
	Gross carrying amount		Accumulated amortization		Gross carrying amount		Accumulated amortization
Insurance and other	$	40,267	$	8,342	$	40,225	$          7,707
Railroad, utilities and energy		1,018		349		988	324
	$	41,285	$	8,691	$	41,213	$          8,031
Trademarks and trade names	$	5,398	$	729	$	5,381	$             692
Patents and technology		4,380		2,635		4,341	2,493
Customer relationships		28,335		4,140		28,322	3,722
Other		3,172		1,187		3,169	1,124
	$	41,285	$	8,691	$	41,213	$          8,031

Amortization expense in the first six months was $707 million in 2018 and $740 million in 2017. Intangible assets with indefinite lives were approximately $18.9 billion as of June 30, 2018 and December 31, 2017.