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Accounting Policies - CECL Table (Details 2) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Allowance for doubtful accounts | $ 15,358 | $ 8,497
Accounts Receivable, Credit Loss Expense (Reversal) | 10,985 |
Accounts Receivable, Allowance for Credit Loss, Writeoff | 5,306 |
Accounts Receivable, Allowance for Credit Loss, Recovery | 1,182 |
Electric |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Allowance for doubtful accounts | 899 | 328
Accounts Receivable, Credit Loss Expense (Reversal) | 1,517 |
Accounts Receivable, Allowance for Credit Loss, Writeoff | 1,289 |
Accounts Receivable, Allowance for Credit Loss, Recovery | 343 |
Natural gas distribution |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Allowance for doubtful accounts | 2,571 | 1,056
Accounts Receivable, Credit Loss Expense (Reversal) | 3,187 |
Accounts Receivable, Allowance for Credit Loss, Writeoff | 2,511 |
Accounts Receivable, Allowance for Credit Loss, Recovery | 839 |
Pipeline |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Allowance for doubtful accounts | 2 | 0
Accounts Receivable, Credit Loss Expense (Reversal) | 2 |
Accounts Receivable, Allowance for Credit Loss, Writeoff | 0 |
Accounts Receivable, Allowance for Credit Loss, Recovery | 0 |
Construction materials and contracting |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Allowance for doubtful accounts | 6,164 | 5,357
Accounts Receivable, Credit Loss Expense (Reversal) | 1,447 |
Accounts Receivable, Allowance for Credit Loss, Writeoff | 640 |
Accounts Receivable, Allowance for Credit Loss, Recovery | 0 |
Construction services |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Allowance for doubtful accounts | 5,722 | $ 1,756
Accounts Receivable, Credit Loss Expense (Reversal) | 4,832 |
Accounts Receivable, Allowance for Credit Loss, Writeoff | 866 |
Accounts Receivable, Allowance for Credit Loss, Recovery | $ 0 |

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