Capital Stock - Non-redeemable Non-controlling Interests (Details)	Dec. 31, 2021	Dec. 31, 2020
Trivago
Noncontrolling Interest [Line Items]
Ownership interest percentage	58.30%	59.00%

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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