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v3.21.1

Securities (Narrative) (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 USD ($) security | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($) security
Unrealized Loss |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 291 |  | 104
Available-for-sale debt securities, in gross unrealized loss position | $ 0 |  | $ 0
Available-for-sale, allowance for credit loss | 0 |  | $ 0
Provision for credit losses | 0 | $ 73,870,000 |
AFS debt securities |  |  |
Unrealized Loss |  |  |
Provision for credit losses | $ 0 | $ 0 |
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities |  |  |
Unrealized Loss |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 112 |  | 46
U.S. government-sponsored enterprises debt securities |  |  |
Unrealized Loss |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 41 |  |
Corporate debt securities |  |  |
Unrealized Loss |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 26 |  | 17
AFS debt securities |  |  |
Unrealized Loss |  |  |
AFS debt securities, accrued interest | $ 22,900,000 |  | $ 22,300,000

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