Investment Securities - Fair Value of Other Securities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt and Equity Securities, FV-NI [Line Items]
Bonds	$ 35	$ 40
Other long-term investments	0	1
Total	75	86
Non-U.S. government and government sponsored entities
Debt and Equity Securities, FV-NI [Line Items]
Bonds	1	1
Corporate debt
Debt and Equity Securities, FV-NI [Line Items]
Bonds	17	24
Mortgage-backed, asset-backed, and collateralized bonds
Debt and Equity Securities, FV-NI [Line Items]
Bonds	17	15
Preferred stock
Debt and Equity Securities, FV-NI [Line Items]
Equity securities	13	19
Common stock
Debt and Equity Securities, FV-NI [Line Items]
Equity securities	$ 27	$ 26

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

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Amount of long-term investments classified as other.

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

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