Goodwill and Other Intangible Assets - Rollforward of Goodwill by Operating Segment (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Goodwill, beginning balance	$ 9,618	$ 9,638	$ 8,548
Acquisitions	201	0	1,073
Adjustments	(1)	(20)	17
Goodwill, ending balance	9,818	9,618	$ 9,638
CB-Retail
Goodwill [Line Items]
Goodwill, beginning balance	3,724
Acquisitions	0
Adjustments	0
Goodwill, ending balance	3,724	3,724
CB-Commercial
Goodwill [Line Items]
Goodwill, beginning balance	3,862
Acquisitions	0
Adjustments	0
Goodwill, ending balance	3,862	3,862
FS&CF
Goodwill [Line Items]
Goodwill, beginning balance	259
Acquisitions	0
Adjustments	(1)
Goodwill, ending balance	258	259
IH
Goodwill [Line Items]
Goodwill, beginning balance	1,773
Acquisitions	201
Adjustments	0
Goodwill, ending balance	$ 1,974	$ 1,773

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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