The description of the method of settlement (for example, whether in cash or equity) for a type of share-based payment arrangement that existed at any time during the period. An entity with substantially similar types of share-based payment arrangements may aggregate this information. [Refer: Share-based payment arrangements [member]]

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The description of the vesting requirements for a type of share-based payment arrangement that existed at any time during the period. An entity with substantially similar types of share-based payment arrangements may aggregate this information. [Refer: Share-based payment arrangements [member]]

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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The exercise price of outstanding share options.

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The amount of liabilities arising from share-based payment transactions. Share-based payment transactions are transactions in which the entity: (a) receives goods or services from the supplier of those goods or services (including an employee) in a share-based payment arrangement; or (b) incurs an obligation to settle the transaction with the supplier in a share-based payment arrangement when another group entity receives those goods or services. [Refer: Share-based payment arrangements [member]]

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Number of global mining comparators

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Number of shares cash-settled awards outstanding in share-based payment arrangement.

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Percentage of cancellations employees electing to withdraw their investment shares before vesting.

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Percentage of forfeitures, prior to vesting, on outstanding awards.

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Percentage of share-based payment charge for plan.

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Share-based payments - Additional information (Detail)	12 Months Ended
Share-based payments - Additional information (Detail)	Dec. 31, 2020 Instrument £ / shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2020 USD ($) shares
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of cancellations employees electing to withdraw their investment shares before vesting of their matching shares	15.00%
Liability for cash-settled awards \| $		$ 19,000,000	$ 7,000,000
Rio Tinto plc
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of share-based payment charge for plan	100.00%	100.00%
Rio Tinto Limited
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of share-based payment charge for plan	100.00%	100.00%
Performance share plans
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of forfeitures, prior to vesting, on outstanding awards	5.00%	5.00%
Description of vesting requirements for share-based payment arrangement	Forfeitures prior to vesting are assumed at 5% per annum of outstanding awards (2017: 5% per annum).
Number of global mining comparators \| Instrument	10
Performance share plans \| Rio Tinto plc
Disclosure of terms and conditions of share-based payment arrangement [line items]
Cash-settled awards outstanding \| shares			48,191
Liability for cash-settled awards \| $			$ 3,000,000
Performance share plans \| Rio Tinto plc \| Top of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Cash-settled awards outstanding \| shares		49,019
Liability for cash-settled awards \| $		$ 13,000,000
Performance share plans \| Rio Tinto Limited
Disclosure of terms and conditions of share-based payment arrangement [line items]
Cash-settled awards outstanding \| shares		276,722	15,164
Management share plans
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of forfeitures, prior to vesting, on outstanding awards	7.00%	7.00%
Description of vesting requirements for share-based payment arrangement	The vesting of these awards is dependent on service conditions being met.
Bonus deferral plans
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of method of settlement for share-based payment arrangement	3	3
Description of vesting requirements for share-based payment arrangement	The vesting of these awards is dependent only on service conditions being met.
Global employee share plans
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of forfeitures, prior to vesting, on outstanding awards	5.00%	5.00%
Description of vesting requirements for share-based payment arrangement	The vesting of these matching awards is dependent on service conditions being met and the continued holding of investment shares by the participant until vesting.
Share Incentive Plans
Disclosure of terms and conditions of share-based payment arrangement [line items]
Liability for cash-settled awards \| $			$ 4,000,000
Share Incentive Plans \| Top of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Liability for cash-settled awards \| $		$ 6,000,000
Share Incentive Plans \| Rio Tinto plc
Disclosure of terms and conditions of share-based payment arrangement [line items]
Cash-settled awards outstanding \| shares		52,881	89,253
Share Incentive Plans \| Rio Tinto Limited
Disclosure of terms and conditions of share-based payment arrangement [line items]
Cash-settled awards outstanding \| shares		81,050	14,878
Executive Directors And Product Group Executives \| Bonus deferral plans
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of method of settlement for share-based payment arrangement	50
Description of vesting requirements for share-based payment arrangement	50% of the bonuses
Other Executives \| Bonus deferral plans
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of method of settlement for share-based payment arrangement	25
Ranges Of Exercise Prices For Outstanding Share Options Three \| Share Option Plan \| Rio Tinto plc \| Bottom of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Exercise price of outstanding share options \| £ / shares	£ 16
Ranges Of Exercise Prices For Outstanding Share Options Three \| Share Option Plan \| Rio Tinto plc \| Top of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Exercise price of outstanding share options \| £ / shares	25
Ranges Of Exercise Prices For Outstanding Share Options Four \| Share Option Plan \| Rio Tinto Limited
Disclosure of terms and conditions of share-based payment arrangement [line items]
Exercise price of outstanding share options \| £ / shares	£ 33