Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
ASU 2018-12
Reinsurance recoverable	$ 698		$ 665
Prepaid reinsurance premiums	57		51
Deferred policy acquisition costs	1,048	$ 984	1,013	$ 916
Total assets	30,474		29,732
Life policy and investment contract reserves	3,059		3,015
Deferred income tax	1,104		1,054
Total liabilities	19,733		19,170
Retained earnings	11,818		11,711
Accumulated other comprehensive income	(527)		(614)
Total shareholders' equity	10,741	11,912	10,562
Total liabilities and shareholders' equity	30,474		29,732
Earned premiums	1,918	1,693
Insurance losses and contract holders' benefits	1,398	1,032
Underwriting, acquisition and insurance expenses	556	520
Deferred	27	(126)
Net Income (Loss)	225	(266)
Change in life policy reserves, reinsurance recoverable and other, net of tax (benefit) of $(9) and $41, respectively	(36)	155
Other comprehensive income (loss)	87	(434)
Comprehensive Income (Loss)	$ 312	$ (700)
Basic (in USD per share)	$ 1.43	$ (1.66)
Diluted (in USD per share)	$ 1.42	$ (1.66)
Accounting Standards Update 2018-12
ASU 2018-12
Reinsurance recoverable			665		$ 287
Prepaid reinsurance premiums			51
Deferred policy acquisition costs			1,013		296
Total assets			29,732
Life policy and investment contract reserves			3,015
Deferred income tax			1,054
Total liabilities			19,170
Retained earnings			11,711
Accumulated other comprehensive income			(614)
Total shareholders' equity			10,562
Total liabilities and shareholders' equity			29,732
Earned premiums		$ 1,693
Insurance losses and contract holders' benefits		1,032
Underwriting, acquisition and insurance expenses		520
Deferred		(126)
Net Income (Loss)		(266)
Change in life policy reserves, reinsurance recoverable and other, net of tax (benefit) of $(9) and $41, respectively		(155)
Other comprehensive income (loss)		(434)
Comprehensive Income (Loss)		$ (700)
Basic (in USD per share)		$ (1.66)
Diluted (in USD per share)		$ (1.66)
Accounting Standards Update 2018-12 | As originally reported
ASU 2018-12
Reinsurance recoverable			640		217
Prepaid reinsurance premiums			79
Deferred policy acquisition costs			1,014		263
Total assets			29,736
Life policy and investment contract reserves			3,059
Deferred income tax			1,045
Total liabilities			19,205
Retained earnings			11,702
Accumulated other comprehensive income			(636)
Total shareholders' equity			10,531
Total liabilities and shareholders' equity			29,736
Earned premiums		$ 1,690
Insurance losses and contract holders' benefits		1,039
Underwriting, acquisition and insurance expenses		519
Deferred		(128)
Net Income (Loss)		(273)
Change in life policy reserves, reinsurance recoverable and other, net of tax (benefit) of $(9) and $41, respectively		0
Other comprehensive income (loss)		(589)
Comprehensive Income (Loss)		$ (862)
Basic (in USD per share)		$ (1.70)
Diluted (in USD per share)		$ (1.70)
Accounting Standards Update 2018-12 | Effect of Modified Retrospective Application Accounting Standards Update 2018-12
ASU 2018-12
Reinsurance recoverable			25
Prepaid reinsurance premiums			(28)
Deferred policy acquisition costs			(1)		$ 33
Total assets			(4)
Life policy and investment contract reserves			(44)
Deferred income tax			9
Total liabilities			(35)
Retained earnings			9
Accumulated other comprehensive income			22
Total shareholders' equity			31
Total liabilities and shareholders' equity			$ (4)
Earned premiums		$ 3
Insurance losses and contract holders' benefits		(7)
Underwriting, acquisition and insurance expenses		1
Deferred		2
Net Income (Loss)		7
Change in life policy reserves, reinsurance recoverable and other, net of tax (benefit) of $(9) and $41, respectively		(155)
Other comprehensive income (loss)		155
Comprehensive Income (Loss)		$ 162
Basic (in USD per share)		$ 0.04
Diluted (in USD per share)		$ 0.04