Investments, Debt and Securities [Line Items]

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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- Definition

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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Investments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
Investments (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Investments, Debt and Securities [Line Items]
Net income from unconsolidated investees	$ 54	$ 15		$ 97	$ 71
OCC, Prior Period Results
Investments, Debt and Securities [Line Items]
Net income from unconsolidated investees			$ 36		$ 71
OCC
Investments, Debt and Securities [Line Items]
Equity method investment, ownership percentage	40.00%	40.00%		40.00%	40.00%
Foreign Government Debt Securities
Investments, Debt and Securities [Line Items]
Trading securities	$ 157			$ 157		$ 169