XML 69 R57.htm IDEA: XBRL DOCUMENT v3.23.3
Components of Retirement Plan Costs (Detail) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2023
Sep. 30, 2022
Sep. 30, 2023
Sep. 30, 2022
Pension Plan [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Service Cost $ 522 $ 792 $ 1,568 $ 2,374
Interest Cost 1,870 1,372 5,610 4,114
Expected Return on Plan Assets (2,673) (2,722) (8,017) (8,162)
Prior Service Cost Amortization 90 89 267 267
Actuarial Loss Amortization   1,376   4,130
Sub-total (191) 907 (572) 2,723
Amounts Capitalized and Deferred 333 (345) 1,197 (810)
Net Periodic Benefit Cost Recognized 142 562 625 1,913
Other Postretirement Benefits Plan [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Service Cost 374 723 1,120 2,167
Interest Cost 724 798 2,174 2,396
Expected Return on Plan Assets (852) (853) (2,556) (2,561)
Prior Service Cost Amortization 198 273 595 819
Actuarial Loss Amortization (366) 255 (1,098) 765
Sub-total 78 1,196 235 3,586
Amounts Capitalized and Deferred 82 (655) 415 (1,788)
Net Periodic Benefit Cost Recognized 160 541 650 1,798
Supplemental Employee Retirement Plan [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Service Cost 63 69 188 205
Interest Cost 188 118 565 354
Prior Service Cost Amortization 14 14 42 42
Actuarial Loss Amortization   196   595
Sub-total 265 397 795 1,196
Amounts Capitalized and Deferred (82) (117) (246) (354)
Net Periodic Benefit Cost Recognized $ 183 $ 280 $ 549 $ 842