Long-Term Debt and Note Payable - Affiliate - Schedule of Debt Maturity (Details) $ in Millions	Dec. 31, 2020 USD ($)
Maturities of long-term debt (excluding unamortized premiums and discounts and unamortized debt issuance costs and other and excluding note payable-affiliate)
2021	$ 951
2022	1
2023	1
2024	1
2025	251
2026 and thereafter	2,186
Total long-term debt	$ 3,391

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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