Other Commitments and Contingencies - Additional Information (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)
Subsequent Event [Line Items]
Intercompany Agreements, Description	three years
Debt Service Coverage Ratio	1.25
Time to cure ratio	5 days
Ratio based on average number of prior quarters	6
Funds from operations interest coverage ratio minimum times	2
Total debt to capital maximum	65
Number Of Years to Collect Benefits	20 years
Total purchase obligations for 2018	$ 69,459
Total purchase obligations for 2019 - 2020	81,841
Total purchase obligations for 2021 - 2022	69,420
Total purchase obligations thereafter	201,504
Aggregate guaranteed amount	20,000
Guarantor Obligations, Current Carrying Value	5,700
Amount of letter of credit to our current primary insurance company	$ 4,800
Florida Natural Gas Distribution and Eight Flags [Member]
Subsequent Event [Line Items]
Number of Years for Asset Management Agreement	10 years

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Maximum days to make default good.

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Maximum debt to net capital ratio under agreement two.

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Minimum interest coverage ratio under agreement two.

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Number Of Years to Collect Benefits

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Number of Years for Asset Management Agreement

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Ratio based on average number of prior quarters

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- Definition

Standby Letters Of Credit

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Description of product support, consulting, business, or other advisory service agreements entered into between the managing member or general partner and the LLC or LP, affiliate of the managing member or general partner, or affiliate of the LLC or LP. Includes a description of the key provisions of such agreements and the amount of compensation for such services during the accounting period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 850
-SubTopic 10
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Amount of purchase arrangement to be paid after fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in fourth and fifth fiscal years following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in next fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in second and third fiscal years following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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