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Acquisitions Acquisitions (narrative) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Business Acquisition [Line Items] |  |
Payments for Other Deposits | $ 1,550 | $ 0
CHINA | Huatai Group [Member] |  |
Business Acquisition [Line Items] |  |
Payments for Other Deposits | $ 1,550 |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of cash outflow for deposits classified as other. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585 + Details
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- Details
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- Details
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