Significant Accounting Policies - Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Mar. 31, 2021
Inventory
Propane	$ 111,648	$ 45,521
Crude oil	87,923	64,916
Total	319,895	158,467
Butane Inventory
Inventory
Energy Related Inventory, Natural Gas Liquids	88,163	19,189
Biodiesel Inventory
Inventory
Renewable Energy Related Inventory	12,658	16,169
Diesel Inventory
Inventory
Energy Related Inventory, Crude Oil, Products and Merchandise	5,742	2,252
Ethanol Inventory
Inventory
Renewable Energy Related Inventory	2,802	3,056
Other natural gas liquids
Inventory
Energy Related Inventory, Natural Gas Liquids	$ 10,959	$ 7,364

Renewable Energy Related Inventory

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

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Carrying amount as of the balance sheet date of petroleum or crude oil.

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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.

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