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Derivatives and Hedging - Schedule of Derivative Gains (Losses) Recognized in the Consolidated Financial Statements (Details) - Foreign exchange contracts - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
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Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Derivative [Line Items] |  |  |  |
(Loss) gain recognized in Accumulated other comprehensive loss | $ (2) | $ (2) | $ 11 | $ (13)
Derivative gains (losses) reclassified from accumulated other comprehensive loss | 0 | (6) | (1) | (11)
Total revenue |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative gains (losses) reclassified from accumulated other comprehensive loss | 0 | (5) | (1) | (9)
Compensation and benefits |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative gains (losses) reclassified from accumulated other comprehensive loss | 0 | (1) | 0 | (1)
Interest expense |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative gains (losses) reclassified from accumulated other comprehensive loss | $ 0 | $ 0 | $ 0 | $ (1)

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- Definition Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=121577181&loc=SL110061190-113977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e637-108580 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669646-108580 + Details
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- Definition Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e689-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e637-108580 + Details
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