Derivative Instruments - Fair Values of Derivative Contracts Recorded in Condensed Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands		Jun. 30, 2024	Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Energy Marketing Contracts Assets, Current		$ 1,180	$ 1,027
Energy Marketing Contract Liabilities, Current		27	354
Energy Marketing Contract Liabilities, Total	[1]	39	1,281
Energy Marketing Contracts Assets, Total	[2]	1,372	1,067
Energy Marketing Contract Liabilities Current - fn		100
Mark To Market Energy Assets [Member] | Propane Swap Agreement [Member] | Derivatives designated as hedging instrument [Member]
Derivatives, Fair Value [Line Items]
Energy Marketing Contracts Assets, Current		866	702
Mark To Market Energy Assets [Member] | Interest Rate Swap [Member] | Derivatives designated as hedging instrument [Member]
Derivatives, Fair Value [Line Items]
Energy Marketing Contracts Assets, Current		506	365
Mark-to-market energy liabilities [Member] | Propane Swap Agreement [Member] | Derivatives designated as hedging instrument [Member]
Derivatives, Fair Value [Line Items]
Energy Marketing Contract Liabilities, Current		39	1,078
Mark-to-market energy liabilities [Member] | Interest Rate Swap [Member] | Derivatives designated as hedging instrument [Member]
Derivatives, Fair Value [Line Items]
Energy Marketing Contract Liabilities, Current		$ 0	$ 203

[1] (1) Derivative liabilities, at fair value, included less than $0.1 million in current liabilities in the condensed consolidated balance sheet at June 30, 2024 and $0.4 million at December 31, 2023, with the remainder of the balance classified as long-term.

[2]  (1) Derivative assets, at fair value, include $1.2 million in current assets in the condensed consolidated balance sheet at June 30, 2024 and $1.0 million at December 31, 2023, with the remainder of the balance classified as long-term