Equity Method Investments and Variable Interest Entities (Consolidated Summarized Financial Information - Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Current assets	$ 3,072	$ 3,526
Noncurrent assets	3,219	3,121
Total assets	6,291	6,647
Current liabilities	949	1,277
Noncurrent liabilities	2,922	3,212
Total liabilities	$ 3,871	$ 4,489

The amount of assets reported by an equity method investment of the entity.

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