Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Inventory
Total inventories	$ 548	$ 469	$ 279
Non-utility LPG and natural gas
Inventory
Total inventories	352	278	181
Gas Utility natural gas
Inventory
Total inventories	65	68	19
Energy certificates
Inventory
Total inventories	60	53	3
Materials, supplies and other
Inventory
Total inventories	$ 71	$ 70	$ 76

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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