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v3.22.2.2

Debt and Financing Arrangements - Additional Information (Detail) - USD ($) |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Sep. 29, 2022 | Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021
Line of Credit Facility [Line Items] |  |  |  |  |  |
Weighted average interest rate on short term borrowings |  | 3.60% | 1.20% | 2.40% | 1.20% | 1.20%
Capital lease obligation, current |  | $ 100,000 |  | $ 100,000 |  |
Capital lease obligation, noncurrent |  | 100,000 |  | 100,000 |  |
Accounts Payable |  | 35,200,000 | $ 29,500,000 | 35,200,000 | $ 29,500,000 | $ 52,400,000
Total rental expense under operating leases |  | 500,000 | 500,000 | 1,400,000 | 1,400,000 |
Net Utility Plant |  | 1,303,800,000 | $ 1,237,300,000 | 1,303,800,000 | 1,237,300,000 | 1,257,200,000
Guarantee outstanding |  | 1,600,000 |  | 1,600,000 |  |
Operating lease obligations |  |  |  | 1,400,000 | $ 1,400,000 |
Other current operating lease obligation |  | 1,600,000 |  | 1,600,000 |  |
Other noncurrent operating lease obligation |  | $ 3,000,000 |  | $ 3,000,000 |  |
Operating lease, weighted average remaining lease term |  | 3 years 4 months 24 days | 3 years 8 months 12 days | 3 years 4 months 24 days | 3 years 8 months 12 days |
Operating lease, weighted average discount rate percentage |  | 3.70% | 4.00% | 3.70% | 4.00% |
Guarantee Term Period |  |  |  | 1 year |  |
Assets under Capital Leases [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Net Utility Plant |  | $ 600,000 | $ 700,000 | $ 600,000 | $ 700,000 | 700,000
Net Utility Plant, accumulated amortization |  | $ 300,000 | 300,000 | $ 300,000 | 300,000 | 300,000
Northern Utilities Inc |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Total funded indebtedness as percentage of capitalization |  | 65.00% |  | 65.00% |  |
Natural gas storage inventory |  | $ 23,400,000 | 9,700,000 | $ 23,400,000 | 9,700,000 | 8,300,000
Accounts Payable |  | 300,000 | 100,000 | 300,000 | 100,000 | 1,600,000
Revolving Credit Facility |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Revolving credit facility |  | $ 200,000,000 | $ 120,000,000 | 200,000,000 | $ 120,000,000 | $ 120,000,000
Proceeds from lines of credit |  |  |  | 214,000,000 |  |
Repayments of lines of credit |  |  |  | $ 206,100,000 |  |
Credit Facility | Third Amendment Credit Facility |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Sublimit for the issuance of standby letters of credit | $ 25,000,000 |  |  |  |  |
Revolving credit facility | $ 200,000,000 |  |  |  |  |
Credit Facility | Revolving Credit Facility | Third Amendment Credit Facility |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Line of credit facility expiration date | Sep. 29, 2027 |  |  |  |  |
Credit Facility | Revolving Credit Facility | Third Amendment Credit Facility | Secured Overnight Financing Rate [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Credit facility, daily fluctuating rate of interest | 0.10% |  |  |  |  |
Line of credit outstanding | $ 65,500,000 |  |  |  |  |
Line of credit interest rate during the period | 4.272% |  |  |  |  |
Credit Facility | Revolving Credit Facility | Third Amendment Credit Facility | Secured Overnight Financing Rate [Member] | Maximum [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Credit facility, daily fluctuating rate of interest | 1.375% |  |  |  |  |
Debt instrument variable interest rate additional spread | 1.375% |  |  |  |  |
Credit Facility | Revolving Credit Facility | Third Amendment Credit Facility | Secured Overnight Financing Rate [Member] | Minimum [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Credit facility, daily fluctuating rate of interest | 1.125% |  |  |  |  |
Debt instrument variable interest rate additional spread | 1.125% |  |  |  |  |

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- Definition Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(a)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 852 -SubTopic 10 -Section 55 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=84165509&loc=d3e56426-112766 + Details
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