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Other Financial Data - Schedule of Other Non-current Assets (Details) - USD ($) $ in Millions | Sep. 30, 2019 | Dec. 31, 2018
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Other Financial Data [Abstract] |  |
Cost to obtain contracts with customers | $ 163 | $ 156
Taxes receivable | 100 | 100
Leases | 106 |
Investments | 52 | 54
Other | 141 | 138
Total | $ 562 | $ 448

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- Definition Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as noncurrent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130533-203044 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044 + Details
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