Contingency under Credit Agreement, Availability Threshold, Percent

No definition available.

Name:	mat_ContingencyunderCreditAgreementAvailabilityThresholdPercent
Namespace Prefix:	mat_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contingency under Credit Agreement, Excess Availability under Credit Facility

+ References

No definition available.

+ Details

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

- Definition

Fixed Charge Coverage Ratio for Covenant Compliance

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentAxis=mat_CreditAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
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Balance Type:
Period Type:

- Details

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- Details

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- Details

Name:	srt_RangeAxis=srt_MaximumMember
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- Details

Name:	us-gaap_CreditFacilityAxis=mat_RevolvingCreditFacilityAssetBasedMember
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- Details

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Seasonal Financing (Details)		6 Months Ended
Seasonal Financing (Details)	Dec. 20, 2017 USD ($) trading_day	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2019 USD ($)
Debt Instrument [Line Items]
Short-term borrowings		$ 400,000,000	$ 0	$ 45,000,000
Outstanding borrowings			0	0
Credit Agreement
Debt Instrument [Line Items]
Outstanding letters of credit		13,000,000	$ 55,000,000	$ 70,000,000
Revolving Credit Facility \| Credit Agreement
Debt Instrument [Line Items]
Aggregate commitment under the credit facility		1,600,000,000
Interest coverage ratio minimum for covenant compliance	1.00
Excess availability under credit facility	$ 100,000,000	$ 100,000,000
Availability threshold (as a percent)	10.00%
Threshold consecutive trading days \| trading_day	30
Revolving Credit Facility \| Credit Agreement \| Minimum \| LIBOR
Debt Instrument [Line Items]
Interest rate margin for loans (as a percent)		1.25%
Revolving Credit Facility \| Credit Agreement \| Minimum \| Base Rate
Debt Instrument [Line Items]
Interest rate margin for loans (as a percent)		0.25%
Revolving Credit Facility \| Credit Agreement \| Maximum \| LIBOR
Debt Instrument [Line Items]
Interest rate margin for loans (as a percent)		2.75%
Revolving Credit Facility \| Credit Agreement \| Maximum \| Base Rate
Debt Instrument [Line Items]
Interest rate margin for loans (as a percent)		1.75%
Revolving Credit Facility, Asset Based \| Credit Agreement
Debt Instrument [Line Items]
Aggregate commitment under the credit facility		$ 1,310,000,000
Revolving Credit Facility, Secured \| Credit Agreement
Debt Instrument [Line Items]
Aggregate commitment under the credit facility		$ 294,000,000.0