Commitments and Contingencies - Pledged Assets and Funds in Trust (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
AFS securities	$ 11,264	$ 9,369
Debt Securities, Trading, Restricted	51	45
Equity securities	20	22
Investment funds	90	84
Derivative assets pledged as collateral	96	105
Mortgage loans	4,888	2,535
Short-term investments	108	92
Other investments	104	88
Restricted cash	1,281	402
Total restricted assets	$ 17,902	$ 12,742

Derivative assets pledged as collateral

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- Definition

Investment Funds Pledged as Collateral

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- Definition

Other Investments Pledged as Collateral

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- Definition

Short Term Investments Pledged as Collateral

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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amount of restricted investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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-Topic 944
-SubTopic 210
-Section S99
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Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

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