Inventories Table - Inventory Balances (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Inventory, Net [Abstract]
Other Inventory, Supplies, Gross	$ 456	$ 448
Natural gas, NGLs, and refined products	463	833
Energy Related Inventory, Crude Oil, Products and Merchandise	105	251
Inventory, Net	$ 1,024	$ 1,532	$ 1,372

Carrying amount as of the balance sheet date of natural gas in storage, which is a mixture of gases (liquefied or otherwise), used for fuel and manufacturing purposes, which is ready for sale.

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Carrying amount as of the balance sheet date of finished goods inventories for petroleum products, crude oil, petrochemical products, and other oil and gas inventories.

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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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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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