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Goodwill and Intangible Assets - Goodwill Attributable to Each Business Segments (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Goodwill [Roll Forward] |  |  |
Goodwill, beginning balance | $ 14,544 | $ 14,533 | $ 14,519
Acquisitions | 107 | 33 | 6
Reductions in goodwill related to divestitures | (1) | (17) |
Other adjustments | 3 | (5) | 8
Goodwill, ending balance | 14,653 | 14,544 | 14,533
Credit Card |  |  |
Goodwill [Roll Forward] |  |  |
Goodwill, beginning balance | 5,060 | 5,032 | 5,018
Acquisitions | 25 | 33 | 6
Reductions in goodwill related to divestitures | 0 | 0 |
Other adjustments | 3 | (5) | 8
Goodwill, ending balance | 5,088 | 5,060 | 5,032
Consumer Banking |  |  |
Goodwill [Roll Forward] |  |  |
Goodwill, beginning balance | 4,600 | 4,600 | 4,600
Acquisitions | 46 | 0 | 0
Reductions in goodwill related to divestitures | (1) | 0 |
Other adjustments | 0 | 0 | 0
Goodwill, ending balance | 4,645 | 4,600 | 4,600
Commercial Banking |  |  |
Goodwill [Roll Forward] |  |  |
Goodwill, beginning balance | 4,884 | 4,901 | 4,901
Acquisitions | 36 | 0 | 0
Reductions in goodwill related to divestitures | 0 | (17) |
Other adjustments | 0 | 0 | 0
Goodwill, ending balance | $ 4,920 | $ 4,884 | $ 4,901

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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- Definition Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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- Definition Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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