Significant Accounting Policies - Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026
Inventory
Crude oil	$ 24,274	$ 25,173
Propane	10,911	7,320
Total	67,672	67,351
Butane inventory
Inventory
Energy Related Inventory, Natural Gas Liquids	24,473	26,200
Other natural gas liquids
Inventory
Energy Related Inventory, Natural Gas Liquids	$ 8,014	$ 8,658

Carrying amount as of the balance sheet date of liquid hydrocarbon components recovered from natural gas.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Carrying amount as of the balance sheet date of petroleum or crude oil.

+ References

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Carrying amount as of the balance sheet date of product derived from petroleum during the processing of oil or natural gas which is then used as a heat source or fuel.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480657/210-10-S50-3

Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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