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Subsequent Events (Details) - Subsequent Event	12 Months Ended
	Dec. 31, 2020	Feb. 24, 2020
China
Subsequent Event [Line Items]
Decline in near-term demand due to Level 4 travel advisory		100.00%
China | Forecast
Subsequent Event [Line Items]
Percent of planned capacity impacted by Level 4 travel advisory	5.00%
Other Trans-Pacific Countries
Subsequent Event [Line Items]
Decline in near-term demand due to Level 4 travel advisory		75.00%
Other Trans-Pacific Countries | Forecast
Subsequent Event [Line Items]
Percent of planned capacity impacted by Level 4 travel advisory	10.00%

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- Definition

Increase (Decrease) In Demand Due To Travel Restrictions

+ References

No definition available.

+ Details

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- Definition

Percent Of Planned Capacity Impacted By Travel Advisory

+ References

No definition available.

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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X

- Details

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- Details

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