Partnerships and Joint Ventures - Ownership and Receivables (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Variable interest entity information
Investments	$ 607	$ 886
CFHI
Variable interest entity information
Investments	$ 112	376
Partnership \| Majority
Variable interest entity information
Entity's interest in partnership or joint venture (as a percent)	50.00%
Joint ventures \| Majority
Variable interest entity information
Entity's interest in partnership or joint venture (as a percent)	50.00%
Unconsolidated variable interest entities \| Accounts and notes receivable, net
Variable interest entity information
Receivables related to work performed for unconsolidated partnerships and joint ventures	$ 123	148
Notes receivable	$ 31	$ 27

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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