Share-Based Payments - Additional Information (Detail)	12 Months Ended
Dec. 31, 2017 USD ($) Age $ / shares shares	Dec. 31, 2016 USD ($) $ / shares	Dec. 31, 2015 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, plus other considerations, used to determine the maximum number of shares of common stock available for grant under the Mattel, Inc. 2010 Equity and Long-Term Compensation Plan \| shares	77,000,000
Remaining number of shares of common stock available for grant under the Mattel, Inc. 2010 Equity and Long-Term Compensation Plan \| shares	9,000,000
Share-based compensation	$ 67,119,000	$ 53,950,000	$ 56,691,000
Total unrecognized compensation cost related to unvested share-based payments	$ 105,500,000
Weighted average period for unrecognized compensation cost expected to be recognized (in years)	2 years 1 month 5 days
Weighted average grant date fair value of stock options granted (USD per share) \| $ / shares	$ 3.37	$ 4.09	$ 1.97
Intrinsic value of stock options exercised	$ 500,000	$ 15,800,000	$ 4,900,000
Intrinsic value of stock options outstanding	$ 0
Weighted average remaining life of stock options outstanding (in years)	7 years 4 months 16 days
Intrinsic value of stock options exercisable	$ 0
Weighted average remaining life of stock options exercisable (in years)	6 years 2 months 20 days
Stock options vested or expected to vest (in shares) \| shares	24,800,000
Intrinsic value of stock options vested or expected to vest	$ 0
Weighted average exercise price of stock options vested or expected to vest (USD per share) \| $ / shares	$ 26.62
Weighted average remaining life of stock options vested or expected to vest (in years)	7 years 5 months 5 days
Approximate stock options vested (in shares) \| shares	5,000,000
Approximate total grant date fair value of stock options vested	$ 14,000,000	13,000,000	12,000,000
Cash received for stock option exercises	$ 1,775,000	34,065,000	14,995,000
Restricted stock units expected to vest (in shares) \| shares	4,600,000
Weighted average grant date fair value of restricted stock units expected to vest (USD per share) \| $ / shares	$ 20.80
Total grant date fair value of restricted stock units vested	$ 57,000,000	53,100,000	43,200,000
Restricted Stock Unit Compensation Expense, Excluding Performance Restricted Stock Unit Compensation Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	55,200,000	40,200,000	41,500,000
Income tax benefits from share-based payment arrangements	$ (4,200,000)	11,500,000	11,000,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
General vesting period	3 years
Age requirement for accelerated vesting \| Age	55
Service period requirement for accelerated vesting	5 years
Accelerated vesting period for individuals who meet the age and service requirements	6 months
Number of shares issued per RSU award (in shares) \| shares	3
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued per RSU award (in shares) \| shares	1
Share-based compensation	$ 14,100,000	10,500,000	15,200,000
Income tax benefits from share-based payment arrangements		6,800,000	5,500,000
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued per RSU award (in shares) \| shares	1
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued per RSU award (in shares) \| shares	3
Nonqualified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum grant date fair value of nonqualified stock options as a percentage of the fair value of Mattel's common stock	100.00%
General vesting period	3 years
Age requirement for accelerated vesting \| Age	55
Service period requirement for accelerated vesting	5 years
Accelerated vesting period for individuals who meet the age and service requirements	6 months
Nonqualified Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option expire from date of grant, period (no later than)	10 years
January 1, 2017 to December 31, 2019 LTIP \| Performance Restricted Stock Unit Compensation Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefits from share-based payment arrangements	$ 0
January 1, 2016 to December 31, 2018 LTIP \| Performance Restricted Stock Unit Compensation Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefits from share-based payment arrangements	0	1,200,000
January 1, 2014 to December 31, 2016 LTIP \| Performance Restricted Stock Unit Compensation Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	0	0	0
Income tax benefits from share-based payment arrangements	$ 0	$ 0	$ 0

Age requirement for accelerated vesting under the 2010 Equity and Long-Term Compensation Plan.

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Number of shares, plus the number of shares that remained available for issuance under the 2005 Equity Compensation Plan on May 12, 2010, and any shares subject to awards outstanding under the 2005 Equity Compensation Plan that on or after May 12, 2010 are forfeited, used to determine the maximum number of shares of common stock available for grant under the Mattel, Inc. 2010 Equity and Long-Term Compensation Plan.

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Unrecognized cost of unvested share-based compensation awards.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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