Long-term Debt - Additional Information (Details) - USD ($) $ in Millions |
12 Months Ended | |
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Dec. 31, 2020 |
Dec. 31, 2019 |
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| Debt Instrument [Line Items] | ||
| Maximum unencumbered assets percentage of unsecured debt | 120.00% | |
| Convertible Notes Payable | 2023 Convertible Notes | ||
| Debt Instrument [Line Items] | ||
| Letters of Credit Outstanding, Amount | $ 294 | |
| Principal | $ 144 | |
| Stated Interest Rate | 0.00% | |
| Convertible Notes Payable | 4.125% Convertible Senior Notes Due September 1, 2022 | ||
| Debt Instrument [Line Items] | ||
| Principal | $ 294 | $ 150 |
| Redemption price, percentage | 100.00% |
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- Definition Debt Covenant, Maximum Unencumbered Assets Percentage Of Unsecured Debt No definition available.
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. No definition available.
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