Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) |
12 Months Ended | |
|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2021 |
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| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||
| Accrued expenses and other current liabilities | $ 226,000,000 | $ 258,000,000 |
| Accrued expenses and other current liabilities | 242,000,000 | 189,000,000 |
| Cumulative-effect benefit to retained earnings | (82,000,000) | 79,000,000 |
| Deferred loyalty program revenue | ||
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||
| Loyalty program liability | 81,000,000 | 109,000,000 |
| Accrued expenses and other current liabilities | 43,000,000 | 67,000,000 |
| Accrued expenses and other current liabilities | 38,000,000 | $ 42,000,000 |
| Cumulative adjustment, increase in loyalty revenues | $ 16,000,000 |
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- Definition Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which (increases) decreases obligation to transfer good or service to customer for which consideration from customer has been received or is due. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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 Amount of liabilities classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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