Commitments and Contingencies - Schedule of Future Minimum Obligations for Purchases of Inventory, Services, and Other (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2020	$ 249,567
2021	54,397
2022	37,943
2023	0
2024	0
Thereafter	0
Total future minimum obligations for purchases of inventory, services, and other	$ 341,907

- Definition

For purchases of inventory, other assets, and services containing provisions for future minimum obligations, the total required obligations due.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Purchases Of Inventory Other Assets And Services Future Minimum Obligations Due After Year Five

+ References

No definition available.

+ Details

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- Definition

For purchases of inventory, other assets, and services containing provisions for future minimum obligations, required obligations due within one year of the balance sheet date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

For purchases of inventory, other assets, and services containing provisions for future minimum obligations, required obligations due within the fifth year of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

For purchases of inventory, other assets, and services containing provisions for future minimum obligations, required obligations due within the fourth year of the balance sheet date.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

For purchases of inventory, other assets and services containing provisions for future minimum obligations, required obligations due within the third year of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	mat_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

For purchases of inventory, other assets. and services containing provisions for future minimum obligations, required obligations due within the second year of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	mat_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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