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Dividends - Summary of dividends per share (Parenthetical) (Detail) - Rio Tinto Limited [member] | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
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Disclosure of Dividends [Line Items] |  |  |
Franked final dividend percentage | 30.00% | 30.00% | 30.00%
Franked Interim dividend percentage | 30.00% | 30.00% | 30.00%

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- Definition Disclosure of Dividends [Line Items] + References No definition available. + Details
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- Definition In this arrangement the shareholder is able to reduce the tax paid on the final dividend by an amount equal to the tax imputation credits. + References No definition available. + Details
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- Definition In this arrangement the shareholder is able to reduce the tax paid on the interim dividend by an amount equal to the tax imputation credits. + References No definition available. + Details
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- Details
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