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Other Financial Data - Schedule of Allowance for Doubtful Accounts (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |
Balance at beginning of period | $ 70 | $ 64
Provision | 9 | 8
Accounts written off, net of recoveries | (8) | (8)
Foreign currency translation and other | 3 | 0
Balance at end of period | 81 | $ 64
Cumulative Effect, Period Of Adoption, Adjustment |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |
Balance at beginning of period | 7 |
Cumulative Effect, Period Of Adoption, Adjustment | Accounting Standards Update 2016-13 |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |
Balance at beginning of period | 7 |
Cumulative Effect, Period Of Adoption, Adjusted Balance |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |
Balance at beginning of period | $ 77 |

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- Definition Amount of allowance for credit loss on accounts receivable, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446 + Details
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