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EMPLOYEE BENEFIT PLANS - Fair Value of Plan Assets (Details) - Defined benefit pension plan - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | ---
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | $ 91,567 | $ 75,823 | $ 81,981
Cash And Cash Equivalents | Quoted Prices In Active Markets For Identical Assets (Level 1) |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 2,958 | 5,277 |
Equities - Global | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 10,028 |  |
Equities - United States large-cap | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 19,220 | 21,862 |
Equities - United States small-cap | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 7,592 | 5,259 |
Equities - International developed markets | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 10,528 | 10,593 |
Equities - International emerging markets | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 8,410 | 4,808 |
Fixed income - Investment grade | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 26,186 | 15,777 |
Fixed income - High yield | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets |  | 4,508 |
Real estate | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | 4,355 | 5,034 |
Pension Plan assets - Other | Net asset value per share |  |  |
Employee Benefit Plans |  |  |
Defined benefit plan, fair value of plan assets | $ 2,290 | $ 2,705 |

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