The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Goodwill and Other Intangible Assets - Changes In The Carrying Amount Of Other Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			$ 2,369	$ 1,613	$ 1,613
Acquisitions					1,007
Acquisitions			(93)
Amortization	$ (59)	$ (48)	(119)	(98)	(226)
Foreign currency translation			(2)		(25)
Ending balance	2,155		2,155		2,369
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			2,218	1,432	1,432
Acquisitions					1,007
Amortization			(104)		(196)
Foreign currency translation			(2)		(25)
Ending balance	2,019		2,019		2,218
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			151	$ 181	181
Acquisitions					0
Acquisitions			0
Amortization			(15)		(30)
Foreign currency translation			0		0
Ending balance	$ 136		136		$ 151
CRD Acquisition
Finite-lived Intangible Assets [Roll Forward]
Acquisitions			$ (93)