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RETIREMENT AND POSTRETIREMENT PLANS (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Retirement and Postretirement Plans [Abstract] |  |
Curtailment loss | $ 1,543 |
Distributions to Retired Participants [Abstract] |  |
Defined contribution plan description | 100% of each employee’s contributions up to 1% of each employee’s compensation plus 50% of each employee’s contributions over 1% but not in excess of 6% of each employee’s compensation for a maximum contribution of 3.5% of a participating employee’s compensation. |
Minimum employee contribution percentage | 1.00% |
Percentage of employer matching contribution | 50.00% |
Threshold limit percentage of employee compensation | 6.00% |
Maximum percentage of annual contribution per employee | 3.50% |
Cash | $ 9,200 |
Market value of Common Stock from Employee Stock Ownership Plan of BMP (000 shares) | $ 2,400 |
Returned to treasury Stock | 41,101 |
Gross lump-sum distribution | $ 11,600 |
Non-cash tax benefit | $ 301 |
Distribution of common stock (in shares) | 88,081 |
BMP Retirement Plan [Member] |  |
Retirement and Postretirement Plans [Abstract] |  |
Planned contributions/benefit payments | $ 0 |
Retirement Plans [Member] | BMP, Employee and Outside Director Retirement Plans [Member] |  |
Net Periodic Benefit Cost [Abstract] |  |
Service cost | 148 |
Interest cost | 249 | $ 183
Expected return on assets | (984) | (428)
Amortization of unrealized loss | 206 | 229
Net periodic benefit credit | (381) | $ (16)
Retirement and Postretirement Plans [Abstract] |  |
Planned contributions/benefit payments | 2,800 |
Actual contributions/benefit payments | 6,200 |
Curtailment loss | $ 1,500 |

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