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Investment Securities (Investments Gross Unrealized Losses and Fair Value) (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | $ 472,722 | $ 29,087
Securities available for sale, Less than 12 months, Unrealized Losses | 6,043 | 68
Securities available for sale, 12 months or longer, Fair Value | 3,637 | 8
Securities available for sale, 12 months or longer, Unrealized Losses | 64 |
Securities available for sale, Fair Value, Total | 476,359 | 29,095
Securities available for sale, Unrealized Losses, Total | 6,107 | 68
Total Securities, Less than 12 months, Fair Value | 472,722 | 29,087
Total Securities, Less than 12 months, Unrealized Losses | 6,043 | 68
Total Securities, 12 months or longer, Fair Value | 3,637 | 8
Total Securities, 12 months or longer, Unrealized Losses | 64 |
Total Securities, Fair Value | 476,359 | 29,095
Total Securities, Unrealized Losses | 6,107 | 68
Collateralized Mortgage Obligations [Member] | Federal National Mortgage Association [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 8,855 |
Securities available for sale, Less than 12 months, Unrealized Losses | 79 |
Securities available for sale, 12 months or longer, Fair Value |  | 8
Securities available for sale, Fair Value, Total | 8,855 | 8
Securities available for sale, Unrealized Losses, Total | 79 |
Collateralized Mortgage Obligations [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 6,700 |
Securities available for sale, Less than 12 months, Unrealized Losses | 47 |
Securities available for sale, Fair Value, Total | 6,700 |
Securities available for sale, Unrealized Losses, Total | 47 |
Mortgage-Backed Securities [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 472,722 | 29,087
Securities available for sale, Less than 12 months, Unrealized Losses | 6,043 | 68
Securities available for sale, 12 months or longer, Fair Value | 3,637 | 8
Securities available for sale, 12 months or longer, Unrealized Losses | 64 |
Securities available for sale, Fair Value, Total | 476,359 | 29,095
Securities available for sale, Unrealized Losses, Total | 6,107 | 68
Mortgage-Backed Securities [Member] | Federal National Mortgage Association [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 212,724 | 18,155
Securities available for sale, Less than 12 months, Unrealized Losses | 2,400 | 44
Securities available for sale, 12 months or longer, Fair Value | 72 |
Securities available for sale, Fair Value, Total | 212,796 | 18,155
Securities available for sale, Unrealized Losses, Total | 2,400 | 44
Mortgage-Backed Securities [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 211,699 | 10,932
Securities available for sale, Less than 12 months, Unrealized Losses | 3,293 | 24
Securities available for sale, 12 months or longer, Fair Value | 3,565 |
Securities available for sale, 12 months or longer, Unrealized Losses | 64 |
Securities available for sale, Fair Value, Total | 215,264 | 10,932
Securities available for sale, Unrealized Losses, Total | 3,357 | $ 24
Mortgage-Backed Securities [Member] | Government National Mortgage Association [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 32,744 |
Securities available for sale, Less than 12 months, Unrealized Losses | 224 |
Securities available for sale, Fair Value, Total | 32,744 |
Securities available for sale, Unrealized Losses, Total | $ 224 |

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