XML 103 R92.htm IDEA: XBRL DOCUMENT v3.21.2
Employee's Pension and Postretirement Benefits - Amounts Accrued and Unfunded Status (Details) - Pension Plans, Defined Benefit [Member] - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Dec. 31, 2020
Amounts Accrued        
Obligation, beginning of period   $ 20,116 $ 18,840 $ 18,840
Interest cost $ 100 54 $ 300 379
Actuarial gain   0   897
Obligation, end of period and unfunded status   $ 20,170   $ 20,116