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Consolidated Statements of Income (Parenthetical) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Net securities gains (losses) (less than for 2018) | $ 20,000,000 | $ 0 | $ 1,000,000
Impairment losses related to securities | 0 | 0 | 0
Other Noninterest Income [Member] |  |  |
Net securities gains (losses) (less than for 2018) | $ 20,000,000 | $ 1,000,000 | $ 1,000,000

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