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Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | ---
Goodwill [Line Items] |  |  |
Expected deductible goodwill for tax purpose | $ 608,000,000 |  |
Consumer Bank [Member] |  |  |
Goodwill [Line Items] |  |  |
Estimated fair value of the Community Bank unit greater than certain percent of carrying value | 76.00% |  |
Accumulated impairment loss | $ 0 | $ 0 | $ 0
Commercial Bank [Member] |  |  |
Goodwill [Line Items] |  |  |
Estimated fair value of the Community Bank unit greater than certain percent of carrying value | 29.00% |  |
Accumulated impairment loss | $ 0 | $ 0 | $ 0
Institutional Bank [Member] |  |  |
Goodwill [Line Items] |  |  |
Estimated fair value of the Community Bank unit greater than certain percent of carrying value | 34.00% |  |

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- Definition Amount of accumulated impairment loss for 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://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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