Goodwill and Other Intangibles (Tables)

6 Months Ended

Jun. 30, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Changes in the Carrying Amount of Goodwill

Changes in the carrying amount of goodwill are as follows:

June 30,
(In millions)	2018			2017
Balance as of January 1,	$	9,089		$	8,369
Goodwill acquired	116			370
Other adjustments(a)	(28		)	82
Balance at June 30,	$	9,177		$	8,821

Amortized Intangible Assets

The gross cost and accumulated amortization at June 30, 2018 and December 31, 2017 are as follows:

	June 30, 2018						December 31, 2017
(In millions)	Gross Cost		Accumulated Amortization		Net Carrying Amount		Gross Cost		Accumulated Amortization		Net Carrying Amount
Client Relationships	$	1,711	$	580	$	1,131	$	1,672	$	518	$	1,154
Other (a)	237		134		103		234		114		120
Amortized intangibles	$	1,948	$	714	$	1,234	$	1,906	$	632	$	1,274

^(a) Primarily non-compete agreements, trade names and developed technology.

Estimated Future Aggregate Amortization Expense

The estimated future aggregate amortization expense is as follows:

For the Years Ending December 31,
(In millions)	Estimated Expense
2018 (excludes amortization through June 30, 2018)	$	94
2019	173
2020	154
2021	143
2022	132
Subsequent years	538
	$	1,234