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Parent Company Condensed Financial Information - Statements of Net Income (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Condensed Income Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total Interest and Dividend Income | $ 75,548 | $ 76,848 | $ 80,479 | $ 87,589 | $ 82,457 | $ 79,813 | $ 79,624 | $ 78,590 | $ 320,464 | $ 320,484 | $ 289,826
Interest expense on long-term debt |  |  |  |  |  |  |  |  | 1,201 | 1,831 | 1,129
Income tax benefit | 5,702 | 3,323 | (11,793) | 2,767 | 5,091 | 4,743 | 5,070 | 4,222 | (1) | 19,126 | 17,845
Net Income | $ 24,176 | $ 16,705 | $ (33,072) | $ 13,231 | $ 22,269 | $ 26,936 | $ 26,101 | $ 22,929 | 21,040 | 98,234 | 105,334
Parent Company |  |  |  |  |  |  |  |  |  |  |
Condensed Income Statements, Captions [Line Items] |  |  |  |  |  |  |  |  |  |  |
Dividends from subsidiaries |  |  |  |  |  |  |  |  | 59,315 | 59,490 | 44,988
Investment income |  |  |  |  |  |  |  |  | 0 | 1 | 24
Total Interest and Dividend Income |  |  |  |  |  |  |  |  | 59,315 | 59,491 | 45,012
Interest expense on long-term debt |  |  |  |  |  |  |  |  | 1,696 | 1,285 | 1,149
Other expenses |  |  |  |  |  |  |  |  | 4,464 | 4,325 | 3,988
Total Expense |  |  |  |  |  |  |  |  | 6,160 | 5,610 | 5,137
Income before income tax and undistributed net income of subsidiaries |  |  |  |  |  |  |  |  | 53,155 | 53,881 | 39,875
Income tax benefit |  |  |  |  |  |  |  |  | (1,315) | (1,189) | (1,093)
Income before undistributed net income of subsidiaries |  |  |  |  |  |  |  |  | 54,470 | 55,070 | 40,968
Equity in undistributed net income (distribution in excess of net income) of bank subsidiary |  |  |  |  |  |  |  |  | (27,529) | 42,683 | 68,385
Equity in undistributed net income (distribution in excess of net income) of nonbank subsidiaries |  |  |  |  |  |  |  |  | (5,901) | 481 | (4,019)
Net Income |  |  |  |  |  |  |  |  | $ 21,040 | $ 98,234 | $ 105,334

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