Commitments and Contingencies - Schedule of Future Minimum Payments for Licensing and Similar Agreements (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2020	$ 85,376
2021	53,653
2022	42,949
2023	1,506
2024	826
Thereafter	0
Total future minimum licensing and similar agreements obligations	$ 184,310

- Definition

For licensing and similar agreements containing provisions for future minimum payments, the total required payments due.

+ References

No definition available.

+ Details

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

- Definition

For licensing and similar agreements containing provisions for future minimum payments, required payments due within one year of the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

For licensing and similar agreements containing provisions for future minimum payments, required payments due within the fifth year of the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

For licensing and similar agreements containing provisions for future minimum payments, required payments due within the fourth year of the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

For licensing and similar agreements containing provisions for future minimum payments, required payments due within the third year of the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

For licensing and similar agreements containing provisions for future minimum payments, required payments due within the second year of the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

For licensing and similar agreements containing provisions for future minimum payments, required payments due after the fifth year of the balance sheet date.

+ References

No definition available.

+ Details

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

- References

No definition available.

+ Details

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