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v3.21.2

Retirement Benefit Plans (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Dec. 31, 2020
Net Periodic Benefit Cost [Line Items] |  |  |  |  |
Interest credit under cash balance plan |  |  | 0.03 |  |
Employer matching contribution, percentage |  |  | 5.00% |  |
Employees' Pension Plan |  |  |  |  |
Net Periodic Benefit Cost [Line Items] |  |  |  |  |
Assumptions used calculating benefit obligation, interest rate to annuitize cash balance account |  |  |  |  | 0.53%
Defined benefit plan, increase in benefit payable, percent | 3.00% |  | 3.00% |  |
Defined benefit plan, benefit obligation, increase (decrease) for plan amendment |  |  | $ 351,638 |  |
Defined benefit plan, amortization of service cost |  |  | 9 years 8 months 12 days |  |
Service Cost | $ 507,000 | $ 401,000 | $ 967,000 | $ 831,000 |
Interest Cost | 343,000 | 355,000 | 683,000 | 772,000 |
Expected Return on Plan Assets | (940,000) | (900,000) | (1,890,000) | (1,804,000) |
Amortization of Prior Service (Credit) Cost | 19,000 | 16,000 | 39,000 | 32,000 |
Amortization of Net Loss (Gain) | 0 | 40,000 | 0 | 41,000 |
Net Periodic (Benefit) Cost | (71,000) | (88,000) | (201,000) | (128,000) |
Plan Contributions During the Period | 0 | 0 | 0 | 0 |
Estimated Future Contributions in the Current Fiscal Year | 0 |  | $ 0 |  |
Select Executive Retirement Plan |  |  |  |  |
Net Periodic Benefit Cost [Line Items] |  |  |  |  |
Assumptions used calculating benefit obligation, interest rate to annuitize cash balance account |  |  |  |  | 2.31%
Defined benefit plan, amortization of service cost |  |  | 12 years 6 months |  |
Defined benefit plan, benefit obligation, period increase (decrease) |  |  | $ 122,797 |  |
Service Cost | 173,000 | 101,000 | 291,000 | 204,000 |
Interest Cost | 50,000 | 42,000 | 95,000 | 96,000 |
Expected Return on Plan Assets | 0 | 0 | 0 | 0 |
Amortization of Prior Service (Credit) Cost | 12,000 | 10,000 | 24,000 | 21,000 |
Amortization of Net Loss (Gain) | 52,000 | 40,000 | 90,000 | 73,000 |
Net Periodic (Benefit) Cost | 287,000 | 193,000 | 500,000 | 394,000 |
Plan Contributions During the Period | 118,000 | 116,000 | 236,000 | 233,000 |
Estimated Future Contributions in the Current Fiscal Year | 236,000 |  | 236,000 |  |
Post-Retirement Benefit Plans |  |  |  |  |
Net Periodic Benefit Cost [Line Items] |  |  |  |  |
Assumptions used calculating benefit obligation, interest rate to annuitize cash balance account |  |  |  |  | 3.09%
Service Cost | 24,000 | 29,000 | 55,000 | 62,000 |
Interest Cost | 57,000 | 77,000 | 124,000 | 155,000 |
Expected Return on Plan Assets | 0 | 0 | 0 | 0 |
Amortization of Prior Service (Credit) Cost | 26,000 | 26,000 | 53,000 | 53,000 |
Amortization of Net Loss (Gain) | (52,000) | (2,000) | (44,000) | 0 |
Net Periodic (Benefit) Cost | 55,000 | 130,000 | 188,000 | 270,000 |
Plan Contributions During the Period | 27,000 | $ 59,000 | 55,000 | $ 137,000 |
Estimated Future Contributions in the Current Fiscal Year | $ 54,000 |  | $ 54,000 |  |
On or Subsequent to January 1, 2003 |  |  |  |  |
Net Periodic Benefit Cost [Line Items] |  |  |  |  |
Service credits, percent of eligible salaries |  |  | 6.00% |  |
Minimum | Prior to January 1, 2003 |  |  |  |  |
Net Periodic Benefit Cost [Line Items] |  |  |  |  |
Service credits, percent of eligible salaries |  |  | 6.00% |  |
Maximum | Prior to January 1, 2003 |  |  |  |  |
Net Periodic Benefit Cost [Line Items] |  |  |  |  |
Service credits, percent of eligible salaries |  |  | 12.00% |  |

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