Investments, Debt and Securities [Line Items]

No definition available.

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- Definition

Amount of other-than-temporary decline in value that has been recognized against investment accounted for under equity method of accounting.

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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

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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- Definition

Amount of investment in equity security without readily determinable fair value.

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- Definition

Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

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- Definition

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

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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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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Investments (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
Investments (Narrative) (Details) - USD ($)	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Investments, Debt and Securities [Line Items]
Equity method investments	$ 614,000,000		$ 614,000,000		$ 512,000,000
Equity securities	173,000,000		173,000,000		175,000,000
Net income (losses) from unconsolidated investees	38,000,000	$ 24,000,000	86,000,000	$ 73,000,000
Impairment of equity method investment	0	0	0	0
Fair value, recurring
Investments, Debt and Securities [Line Items]
Debt securities					28,000,000
Equity securities not have readily determinable fair value		0	17,000,000	0
Gains and losses from equity securities	$ 0	$ 0	$ (13,000,000)	$ 0
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	$ 134,000,000		$ 134,000,000		18,000,000
Corporate debt securities
Investments, Debt and Securities [Line Items]
Debt securities	100,000,000		100,000,000		$ 0
Corporate debt securities \| Fair value, recurring
Investments, Debt and Securities [Line Items]
Debt securities	$ 100,000,000		$ 100,000,000