Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Long-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Mar. 25, 2019	Dec. 21, 2018	Sep. 28, 2018
Debt Instrument [Line Items]
Long-term debt	$ 843	$ 844
Surplus Note Due 2059
Debt Instrument [Line Items]
Debt instrument, stated interest rate	8.07%		8.07%
Long-term debt	$ 412	412
Surplus Note Due Dec 2058
Debt Instrument [Line Items]
Debt instrument, stated interest rate	8.15%			8.15%
Long-term debt	$ 200	200
Surplus Note Due Sep 2058
Debt Instrument [Line Items]
Debt instrument, stated interest rate	7.80%				7.80%
Long-term debt	$ 200	200
Non-recourse Debt Due 2030
Debt Instrument [Line Items]
Debt instrument, stated interest rate	7.028%
Long-term debt	$ 31	$ 32