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Organization and Summary of Significant Accounting Policies - Impact of new accounting pronouncements - Schedule of Adoption of ASU 2016-30 (Details) - USD ($) |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Jul. 01, 2020 | Jun. 30, 2020 | Dec. 31, 2020
As reported under ASU 2016-13 | Loans Receivable |  |  |
Impact of adoption of ASU 2016-13 | $ 2,142,363,000 |  |
As reported under ASU 2016-13 | Allowance for credit losses on loans | Consumer Loan |  |  |
Impact of adoption of ASU 2016-13 | 2,247,000 |  |
As reported under ASU 2016-13 | Allowance for credit losses on loans | Commercial Loan |  |  |
Impact of adoption of ASU 2016-13 | 5,952,000 |  |
As reported under ASU 2016-13 | Allowance for credit losses on loans | Real Estate Loan | Construction Real Estate |  |  |
Impact of adoption of ASU 2016-13 | 1,889,000 |  |
As reported under ASU 2016-13 | Allowance for credit losses on loans | Real Estate Loan | Residential real estate loans |  |  |
Impact of adoption of ASU 2016-13 | 8,396,000 |  |
As reported under ASU 2016-13 | Allowance for credit losses on loans | Real Estate Loan | Commercial Real Estate |  |  |
Impact of adoption of ASU 2016-13 | 15,988,000 |  |
As reported under ASU 2016-13 | Total allowance for credit losses on loans |  |  |
Impact of adoption of ASU 2016-13 | 34,472,000 |  |
As reported under ASU 2016-13 | Total allowance for credit losses on off-balance sheet credit exposures |  |  |
Impact of adoption of ASU 2016-13 | 2,227,000 |  |
As reported prior to ASU 2016-13 | Loans Receivable |  |  |
Impact of adoption of ASU 2016-13 | 2,141,929,000 |  |
As reported prior to ASU 2016-13 | Allowance for credit losses on loans | Consumer Loan |  |  |
Impact of adoption of ASU 2016-13 | 1,182,000 |  |
As reported prior to ASU 2016-13 | Allowance for credit losses on loans | Commercial Loan |  |  |
Impact of adoption of ASU 2016-13 | 4,940,000 |  |
As reported prior to ASU 2016-13 | Allowance for credit losses on loans | Real Estate Loan | Construction Real Estate |  |  |
Impact of adoption of ASU 2016-13 | 2,010,000 |  |
As reported prior to ASU 2016-13 | Allowance for credit losses on loans | Real Estate Loan | Residential real estate loans |  |  |
Impact of adoption of ASU 2016-13 | 4,875,000 |  |
As reported prior to ASU 2016-13 | Allowance for credit losses on loans | Real Estate Loan | Commercial Real Estate |  |  |
Impact of adoption of ASU 2016-13 | 12,132,000 |  |
As reported prior to ASU 2016-13 | Total allowance for credit losses on loans |  |  |
Impact of adoption of ASU 2016-13 | 25,139,000 |  |
As reported prior to ASU 2016-13 | Total allowance for credit losses on off-balance sheet credit exposures |  |  |
Impact of adoption of ASU 2016-13 | 1,959,000 |  |
Impact of adoption ASU 2016-13 |  |  |
Increase to the ACL |  | $ 8,900,000 |
Increase in ACL due to transition from PCI to PCD methodology |  | $ 434,000 |
Adjustment to the reserve for unfunded commitments |  |  | $ 268,000
Retained earnings |  |  | $ 7,200,000
Impact of adoption ASU 2016-13 | Loans Receivable |  |  |
Impact of adoption of ASU 2016-13 | 434,000 |  |
Impact of adoption ASU 2016-13 | Allowance for credit losses on loans | Consumer Loan |  |  |
Impact of adoption of ASU 2016-13 | 1,065,000 |  |
Impact of adoption ASU 2016-13 | Allowance for credit losses on loans | Commercial Loan |  |  |
Impact of adoption of ASU 2016-13 | 1,012,000 |  |
Impact of adoption ASU 2016-13 | Allowance for credit losses on loans | Real Estate Loan | Construction Real Estate |  |  |
Impact of adoption of ASU 2016-13 | (121,000) |  |
Impact of adoption ASU 2016-13 | Allowance for credit losses on loans | Real Estate Loan | Residential real estate loans |  |  |
Impact of adoption of ASU 2016-13 | 3,521,000 |  |
Impact of adoption ASU 2016-13 | Allowance for credit losses on loans | Real Estate Loan | Commercial Real Estate |  |  |
Impact of adoption of ASU 2016-13 | 3,856,000 |  |
Impact of adoption ASU 2016-13 | Total allowance for credit losses on loans |  |  |
Impact of adoption of ASU 2016-13 | 9,333,000 |  |
Impact of adoption ASU 2016-13 | Total allowance for credit losses on off-balance sheet credit exposures |  |  |
Impact of adoption of ASU 2016-13 | $ 268,000 |  |

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