Goodwill and Identifiable Intangible Assets, Net - Schedule of Goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2025 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,381,721
Currency Exchange Rate Impact	8,135
Goodwill, ending balance	1,389,856
North America
Goodwill [Roll Forward]
Goodwill, beginning balance	732,995
Currency Exchange Rate Impact	2,145
Goodwill, ending balance	735,140
International
Goodwill [Roll Forward]
Goodwill, beginning balance	441,155
Currency Exchange Rate Impact	5,990
Goodwill, ending balance	447,145
American Girl
Goodwill [Roll Forward]
Goodwill, beginning balance	207,571
Currency Exchange Rate Impact	0
Goodwill, ending balance	$ 207,571

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details

MATTEL INC /DE/ 10-Q