Revenues (Receivables) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Allowance for credit loss	$ 86	$ 86
Noncurrent receivables origination in 2020	197
Noncurrent receivables origination in 2019	1,020
Noncurrent receivables origination in 2018	491
Noncurrent receivables origination in 2017	218
Noncurrent receivables origination in 2016	41
Noncurrent receivables origination prior to 2016	24
Other Assets [Member]
Disaggregation of Revenue [Line Items]
Noncurrent receivables	$ 2,000	$ 2,150

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

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