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Accounts Receivable (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Accounts Receivable Details [Abstract] |  |  |  |  |
Allowance for doubtful accounts | $ 12 |  | $ 12 |  | $ 17
Allowance for doubtful accounts - receivables not expected to be collected in one year | 47 |  | 47 |  | 51
Receivables Securitization Facility [Abstract] |  |  |  |  |
Total capacity to transfer undivided interests to investors under the receivables securitization facility | 800 |  | $ 800 |  |
Receivables securitization facility maturity date |  |  | 2022-07 |  |
Receivables securitization facility duration |  |  | 3 years |  |
Value of the outstanding undivided interest held by investors under the receivables securitization facility | 0 |  | $ 0 |  | 0
Accounts receivable supporting the undivided interest held by investors | 1,300 |  | 1,300 |  | $ 1,200
Cost of the receivables securitization facility - interest expense | $ 1 | $ 2 | $ 3 | $ 6 |

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- Definition Duration of the receivables securitization facility,in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Interest expense associated with maintaining the receivables securitization facility. + References No definition available. + Details
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- Definition Maturity date the receivables securitization facility, in Year Month format. + References No definition available. + Details
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- Definition Value of the outstanding undivided interest held by investors under the receivables securitization facility. + References No definition available. + Details
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