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Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2020
Accounting Policies [Abstract] |
Financing Receivable, Allowance for Credit Loss | Details of the Company's expected credit losses were as follows:
| Electric | Natural gas distribution | Pipeline | Construction materials and contracting | Construction services | Total
| (In thousands)
At January 1, 2020 | $ | 328 |  | $ | 1,056 |  | $ | — |  | $ | 5,357 |  | $ | 1,756 |  | $ | 8,497 |
Current expected credit loss provision | 1,517 |  | 3,187 |  | 2 |  | 1,447 |  | 4,832 |  | 10,985 |
Less write-offs charged against the allowance | 1,289 |  | 2,511 |  | — |  | 640 |  | 866 |  | 5,306 |
Credit loss recoveries collected | 343 |  | 839 |  | — |  | — |  | — |  | 1,182 |
At December 31, 2020 | $ | 899 |  | $ | 2,571 |  | $ | 2 |  | $ | 6,164 |  | $ | 5,722 |  | $ | 15,358 |
Contract receivable retainage | Amounts representing balances billed but not paid by customers under retainage provisions in contracts at December 31 were as follows:
| 2020 | 2019
| (In thousands)
Short-term retainage* | $ | 100,054 |  | $ | 75,590 |
Long-term retainage** | 2,761 |  | 14,228 |
Total retainage | $ | 102,815 |  | $ | 89,818 |
* Expected to be paid within 12 months or less and included in receivables, net. ** Included in noncurrent assets - other.
Inventories | Inventories at December 31 consisted of:
| 2020 | 2019
| (In thousands)
Aggregates held for resale | $ | 175,782 |  | $ | 147,723 |
Asphalt oil | 28,238 |  | 41,912 |
Materials and supplies | 25,142 |  | 22,512 |
Merchandise for resale | 21,087 |  | 22,232 |
Natural gas in storage (current) | 21,919 |  | 22,058 |
Other | 18,999 |  | 21,970 |
Total | $ | 291,167 |  | $ | 278,407 |
AFUDC and interest capitailized | The amount of AFUDC for the years ended December 31 was as follows:
| 2020 | 2019 | 2018
| (In thousands)
AFUDC - borrowed | $ | 2,640 |  | $ | 2,807 |  | $ | 2,290 |
AFUDC - equity | $ | 1,270 |  | $ | 698 |  | $ | 1,897 |
Schedule of earnings per share reconciliation | A reconciliation of the weighted average common shares outstanding used in the basic and diluted earnings per share calculation was as follows:
| 2020 |  | 2019 |  | 2018 |
| (In thousands)
Weighted average common shares outstanding - basic | 200,502 |  | 198,612 |  | 195,720 |
Effect of dilutive performance share awards | 69 |  | 14 |  | 430 |
Weighted average common shares outstanding - diluted | 200,571 |  | 198,626 |  | 196,150 |
Shares excluded from the calculation of diluted earnings per share | 164 |  | 164 |  | 10 |

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