| Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] | 
    
|   | 
  | 
  Unrealized   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  Net Gain (Loss)   | 
  | 
  | 
  Retiree   | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  on Interest   | 
  | 
  | 
  Health   | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  Rate   | 
  | 
  | 
  Benefit   | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  Swap   | 
  | 
  | 
  Obligation   | 
  | 
  | 
  Total   | 
  | 
 
|   Balance at December 31, 2022   | 
  | 
$ | 
6,115 | 
  | 
  | 
$ | 
3,013 | 
  | 
  | 
$ | 
9,128 | 
  | 
 
|   Other comprehensive gain before reclassifications   | 
  | 
  | 
607 | 
  | 
  | 
  | 
411 | 
  | 
  | 
  | 
1,018 | 
  | 
 
|   Amounts reclassified from accumulated other comprehensive income: (1)   | 
  | 
  | 
(3,391 | 
) | 
  | 
  | 
(399 | 
) | 
  | 
  | 
(3,790 | 
) | 
 
|   Balance at December 31, 2023   | 
  | 
$ | 
3,331 | 
  | 
  | 
$ | 
3,025 | 
  | 
  | 
$ | 
6,356 | 
  | 
 
|   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   (1) Amounts reclassified from accumulated other comprehensive income:   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Amortization of Other Postretirement Benefit items:   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Actuarial gains (a)   | 
  | 
$ | 
(539 | 
) | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Tax expense   | 
  | 
  | 
140 | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Reclassification net of tax   | 
  | 
$ | 
(399 | 
) | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Realized gains on interest rate swaps reclassified to interest expense   | 
  | 
$ | 
(4,583 | 
) | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Tax expense   | 
  | 
  | 
1,192 | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Reclassification net of tax   | 
  | 
$ | 
(3,391 | 
) | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
 
    
|   | 
  | 
  Unrealized   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  Net Loss   | 
  | 
  | 
  Retiree   | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  on Interest   | 
  | 
  | 
  Health   | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  Rate   | 
  | 
  | 
  Benefit   | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  Swap   | 
  | 
  | 
  Obligation   | 
  | 
  | 
  Total   | 
  | 
 
|   Balance at December 31, 2021   | 
  | 
$ | 
(3,524 | 
) | 
  | 
$ | 
2,471 | 
  | 
  | 
$ | 
(1,053 | 
) | 
 
|   Other comprehensive gain before reclassifications   | 
  | 
  | 
8,587 | 
  | 
  | 
  | 
838 | 
  | 
  | 
  | 
9,425 | 
  | 
 
|   Amounts reclassified from accumulated other comprehensive income: (1)   | 
  | 
  | 
1,052 | 
  | 
  | 
  | 
(296 | 
) | 
  | 
  | 
756 | 
  | 
 
|   Balance at December 31, 2022   | 
  | 
$ | 
6,115 | 
  | 
  | 
$ | 
3,013 | 
  | 
  | 
$ | 
9,128 | 
  | 
 
|   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   (1) Amounts reclassified from accumulated other comprehensive income:   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Amortization of Other Postretirement Benefit items:   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Actuarial gains (a)   | 
  | 
$ | 
(400 | 
) | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Tax expense   | 
  | 
  | 
104 | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Reclassification net of tax   | 
  | 
$ | 
(296 | 
) | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Realized losses on interest rate swaps reclassified to interest expense   | 
  | 
$ | 
1,421 | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Tax expense   | 
  | 
  | 
(369 | 
) | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
|   Reclassification net of tax   | 
  | 
$ | 
1,052 | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
 
 
   
 |