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Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Nonrecurring Basis (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
ASSETS MEASURED ON A NONRECURRING BASIS |  |
Impaired loans and leases | $ 76 | $ 42
Accrued income and other assets | 169 | 16
Total assets on a recurring basis at fair value | 245 | 58
Level 1 [Member] |  |
ASSETS MEASURED ON A NONRECURRING BASIS |  |
Impaired loans and leases | 0 | 0
Accrued income and other assets | 0 | 0
Total assets on a recurring basis at fair value | 0 | 0
Level 2 [Member] |  |
ASSETS MEASURED ON A NONRECURRING BASIS |  |
Impaired loans and leases | 0 | 0
Accrued income and other assets | 118 | 0
Total assets on a recurring basis at fair value | 118 | 0
Level 3 [Member] |  |
ASSETS MEASURED ON A NONRECURRING BASIS |  |
Impaired loans and leases | 76 | 42
Accrued income and other assets | 51 | 16
Total assets on a recurring basis at fair value | $ 127 | $ 58

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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