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Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Rate of weighted-average expected volatility for award under share-based payment arrangement.

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- Definition

Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement.

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No definition available.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Stock Incentive Plans - Narrative (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended	3 Months Ended			6 Months Ended
	Mar. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Stock Incentive Plans Narratives [Abstract]
Compensation expense		$ 94		$ 139	$ 172	$ 204
Unrecognized compensation expense		423			$ 423
Weighted-average period for total unrecognized compensation expense for nonvested equity awards					1 year 8 months 12 days
Cruise Stock Incentive Awards
Stock Incentive Plans Narratives [Abstract]
Cash used to settle awards		$ 200	$ 0
Cruise Stock Incentive Awards \| Stock options
Stock Incentive Plans Narratives [Abstract]
Expiration period					10 years
Dividend yield		0.00%		0.00%
Expected volatility rate		57.30%		55.00%
Risk-free interest rate		2.47%		0.78%
Expected option life		6 years 6 months 25 days		6 years 3 months
Cruise Stock Incentive Awards \| Stock options \| Minimum
Stock Incentive Plans Narratives [Abstract]
Service period					4 years
Cruise Stock Incentive Awards \| Stock options \| Maximum
Stock Incentive Plans Narratives [Abstract]
Service period					10 years
Cruise Stock Incentive Awards \| Restricted Stock Units (RSUs)
Stock Incentive Plans Narratives [Abstract]
Numbers of awards that vested immediately (in shares)	31.0
Total units outstanding (in shares)		60.4			60.4		66.2
Cruise Stock Incentive Awards \| Restricted Stock Units (RSUs) \| Maximum
Stock Incentive Plans Narratives [Abstract]
Service period	4 years
Cruise Stock Incentive Awards \| Stock options and RSUs
Stock Incentive Plans Narratives [Abstract]
Compensation expense		$ 158			$ 1,300
Unrecognized compensation expense		$ 1,900			$ 1,900
Weighted-average period for total unrecognized compensation expense for nonvested equity awards					1 year 8 months 12 days
Total units outstanding (in shares)		85.0			85.0