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Pension and other post-retirement benefits- Change in Plan Assets (Details) - Private Equity Funds $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($)
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward] |
Fair value of plan assets, end of year | $ 7,745
Level 3 |
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward] |
Fair value of plan assets, beginning of year | 0
Contributions into funds | 6,726
Unrealized gains | 1,188
Distributions | $ (169)

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