Investments (Internal Credit Rating Disclosure) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 6,583	$ 6,329
High Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	4,139	4,111
Internal Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	2,256	2,069
Average Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	148	109
Watch List [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	4	4
Internal Noninvestment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	36	36
Year Of Origination 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	432
Year Of Origination 2022 | High Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	196
Year Of Origination 2022 | Internal Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	236
Year Of Origination 2022 | Average Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Year Of Origination 2022 | Watch List [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Year Of Origination 2022 | Internal Noninvestment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0
Year Of Origination 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	1,097	1,098
Year Of Origination 2021 | High Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	725	725
Year Of Origination 2021 | Internal Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	366	367
Year Of Origination 2021 | Average Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	6	6
Year Of Origination 2021 | Watch List [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0	0
Year Of Origination 2021 | Internal Noninvestment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0	0
Year Of Origination 2020 [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	673	674
Year Of Origination 2020 [Member] | High Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	375	402
Year Of Origination 2020 [Member] | Internal Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	298	272
Year Of Origination 2020 [Member] | Average Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0	0
Year Of Origination 2020 [Member] | Watch List [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0	0
Year Of Origination 2020 [Member] | Internal Noninvestment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0	0
Year Of Origination 2019 [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	989	1,003
Year Of Origination 2019 [Member] | High Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	629	645
Year Of Origination 2019 [Member] | Internal Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	333	331
Year Of Origination 2019 [Member] | Average Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	27	27
Year Of Origination 2019 [Member] | Watch List [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0	0
Year Of Origination 2019 [Member] | Internal Noninvestment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0	0
Year Of Origination 2018 [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	784	801
Year Of Origination 2018 [Member] | High Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	435	461
Year Of Origination 2018 [Member] | Internal Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	300	301
Year Of Origination 2018 [Member] | Average Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	49	39
Year Of Origination 2018 [Member] | Watch List [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0	0
Year Of Origination 2018 [Member] | Internal Noninvestment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	0	0
Year Of Origination 2017 [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss		645
Year Of Origination 2017 [Member] | High Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss		344
Year Of Origination 2017 [Member] | Internal Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss		296
Year Of Origination 2017 [Member] | Average Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss		5
Year Of Origination 2017 [Member] | Watch List [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss		0
Year Of Origination 2017 [Member] | Internal Noninvestment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss		0
Year Of Origination Prior Periods [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	2,608	2,108
Year Of Origination Prior Periods [Member] | High Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	1,779	1,534
Year Of Origination Prior Periods [Member] | Internal Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	723	502
Year Of Origination Prior Periods [Member] | Average Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	66	32
Year Of Origination Prior Periods [Member] | Watch List [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	4	4
Year Of Origination Prior Periods [Member] | Internal Noninvestment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 36	$ 36