Investments and Cash - Net Investment Income (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Investment Income
Gross investment income	$ 275	$ 304	$ 387
Investment expenses	(6)	(7)	(9)
Net investment income	269	297	378
Externally managed
Net Investment Income
Gross investment income	204	231	273
Loss mitigation securities and other
Net Investment Income
Gross investment income	55	65	114
AssuredIM Funds
Net Investment Income
Gross investment income	$ 16	$ 8	$ 0

Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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Amount of expenses related to the generation of investment income.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

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