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Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Recent Accounting Pronouncements [Abstract] |  |  |
Retained earnings |  | $ 749,056 | $ 696,214
Allowance for credit losses | [1] | 110,000 |
COVID-19 [Member] |  |  |
Recent Accounting Pronouncements [Abstract] |  |  |
Loans in modification programs related to COVID-19 |  | 110,800 |
ASU 2016-13 [Member] |  |  |
Recent Accounting Pronouncements [Abstract] |  |  |
Allowance for credit losses |  | $ 110,000 | 75,999
ASU 2016-13 [Member] | Cumulative Effect Adjustment for ASU Implementation [Member] |  |  |
Recent Accounting Pronouncements [Abstract] |  |  |
Retained earnings |  |  | (4,300)
Allowance for credit losses |  |  | 3,000
Allowance for credit losses on off-balance sheet credit exposure |  |  | 2,800
Deferred tax asset |  |  | $ (1,500)
[1] | Beginning January 1, 2020, calculation is based on current expected loss methodology. Prior to January 1, 2020, calculation was based on incurred loss methodology.

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