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Parent Company Financial Information (Condensed Statements of Financial Condition) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | --- | ---
Condensed Financial Statements Captions Line Items |  |  |  |
Other assets | $ 156,086 | $ 114,296 |  |
Total assets | 4,912,306 | 4,384,178 |  |
Long-term borrowings, net of issuance costs of $1,377 and $727, respectively | 73,623 | 39,273 |  |
Other liabilities | 86,653 | 74,783 |  |
Shareholders’ equity | 468,363 | 438,947 | $ 396,293 | $ 381,177
Total liabilities and shareholders’ equity | 4,912,306 | 4,384,178 |  |
Parent Company [Member] |  |  |  |
Condensed Financial Statements Captions Line Items |  |  |  |
Cash and due from subsidiary | 31,848 | 7,172 |  |
Investment in and receivables due from subsidiary | 511,572 | 471,959 |  |
Other assets | 4,136 | 3,992 |  |
Total assets | 547,556 | 483,123 |  |
Long-term borrowings, net of issuance costs of $1,377 and $727, respectively | 73,623 | 39,273 |  |
Other liabilities | 5,570 | 4,903 |  |
Shareholders’ equity | 468,363 | 438,947 |  |
Total liabilities and shareholders’ equity | $ 547,556 | $ 483,123 |  |

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