Fair Value Measurements - Assets and liabilities measured and carried at fair value in the financial statements (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Assets:
Available for sale (AFS) fixed maturities	$ 10,809	$ 10,357
Trading fixed maturities	30	28
Equity securities	1,022	1,042
Assets of managed investment entities	28,762	28,931
Total assets accounted for at fair value	17,092	16,723
Liabilities:
Liabilities of managed investment entities	23,927	23,919
Total liabilities accounted for at fair value	5,140	5,243
Contingent consideration — acquisitions
Liabilities:
Contingent consideration	23	23
Other liabilities — derivatives
Liabilities:
Derivative liability	5
Variable interest entity, primary beneficiary
Assets:
Assets of managed investment entities	5,231	5,296
Liabilities:
Liabilities of managed investment entities	5,112	5,220
Fixed maturities
Assets:
Available for sale (AFS) fixed maturities	10,809	10,357
Trading fixed maturities	30	28
U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities	209	216
States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities	1,657	1,832
Foreign government
Assets:
Available for sale (AFS) fixed maturities	257	246
Residential MBS
Assets:
Available for sale (AFS) fixed maturities	1,531	960
Commercial MBS
Assets:
Available for sale (AFS) fixed maturities	100	104
Collateralized loan obligations
Assets:
Available for sale (AFS) fixed maturities	1,894	1,643
Other asset-backed securities
Assets:
Available for sale (AFS) fixed maturities	2,657	2,676
Corporate and other
Assets:
Available for sale (AFS) fixed maturities	2,504	2,680
Equity securities
Assets:
Equity securities	1,022	1,042
Level 1
Assets:
Total assets accounted for at fair value	1,026	1,295
Liabilities:
Total liabilities accounted for at fair value	187	384
Level 1 \| Contingent consideration — acquisitions
Liabilities:
Contingent consideration	0	0
Level 1 \| Other liabilities — derivatives
Liabilities:
Derivative liability	0
Level 1 \| Variable interest entity, primary beneficiary
Assets:
Assets of managed investment entities	191	390
Liabilities:
Liabilities of managed investment entities	187	384
Level 1 \| Fixed maturities
Assets:
Available for sale (AFS) fixed maturities	218	226
Trading fixed maturities	0	0
Level 1 \| U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities	208	215
Level 1 \| States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities	0	0
Level 1 \| Foreign government
Assets:
Available for sale (AFS) fixed maturities	0	0
Level 1 \| Residential MBS
Assets:
Available for sale (AFS) fixed maturities	0	0
Level 1 \| Commercial MBS
Assets:
Available for sale (AFS) fixed maturities	0	0
Level 1 \| Collateralized loan obligations
Assets:
Available for sale (AFS) fixed maturities	0	0
Level 1 \| Other asset-backed securities
Assets:
Available for sale (AFS) fixed maturities	0	0
Level 1 \| Corporate and other
Assets:
Available for sale (AFS) fixed maturities	10	11
Level 1 \| Equity securities
Assets:
Equity securities	617	679
Level 2
Assets:
Total assets accounted for at fair value	15,068	14,502
Liabilities:
Total liabilities accounted for at fair value	4,919	4,823
Level 2 \| Contingent consideration — acquisitions
Liabilities:
Contingent consideration	0	0
Level 2 \| Other liabilities — derivatives
Liabilities:
Derivative liability	5
Level 2 \| Variable interest entity, primary beneficiary
Assets:
Assets of managed investment entities	5,028	4,893
Liabilities:
Liabilities of managed investment entities	4,914	4,823
Level 2 \| Fixed maturities
Assets:
Available for sale (AFS) fixed maturities	9,966	9,531
Trading fixed maturities	30	28
Level 2 \| U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities	1	1
Level 2 \| States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities	1,624	1,791
Level 2 \| Foreign government
Assets:
Available for sale (AFS) fixed maturities	257	246
Level 2 \| Residential MBS
Assets:
Available for sale (AFS) fixed maturities	1,520	946
Level 2 \| Commercial MBS
Assets:
Available for sale (AFS) fixed maturities	100	104
Level 2 \| Collateralized loan obligations
Assets:
Available for sale (AFS) fixed maturities	1,894	1,643
Level 2 \| Other asset-backed securities
Assets:
Available for sale (AFS) fixed maturities	2,320	2,398
Level 2 \| Corporate and other
Assets:
Available for sale (AFS) fixed maturities	2,250	2,402
Level 2 \| Equity securities
Assets:
Equity securities	44	50
Level 3
Assets:
Total assets accounted for at fair value	998	926
Liabilities:
Total liabilities accounted for at fair value	34	36
Level 3 \| Contingent consideration — acquisitions
Liabilities:
Contingent consideration	23	23
Level 3 \| Other liabilities — derivatives
Liabilities:
Derivative liability	0
Level 3 \| Variable interest entity, primary beneficiary
Assets:
Assets of managed investment entities	12	13
Liabilities:
Liabilities of managed investment entities	11	13
Level 3 \| Fixed maturities
Assets:
Available for sale (AFS) fixed maturities	625	600
Trading fixed maturities	0	0
Level 3 \| U.S. Government and government agencies
Assets:
Available for sale (AFS) fixed maturities	0	0
Level 3 \| States, municipalities and political subdivisions
Assets:
Available for sale (AFS) fixed maturities	33	41
Level 3 \| Foreign government
Assets:
Available for sale (AFS) fixed maturities	0	0
Level 3 \| Residential MBS
Assets:
Available for sale (AFS) fixed maturities	11	14
Level 3 \| Commercial MBS
Assets:
Available for sale (AFS) fixed maturities	0	0
Level 3 \| Collateralized loan obligations
Assets:
Available for sale (AFS) fixed maturities	0	0
Level 3 \| Other asset-backed securities
Assets:
Available for sale (AFS) fixed maturities	337	278
Level 3 \| Corporate and other
Assets:
Available for sale (AFS) fixed maturities	244	267
Level 3 \| Equity securities
Assets:
Equity securities	$ 361	$ 313

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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