Equity method investment ownership percentage sold.

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- Definition

Gain loss on investments net of tax.

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- Definition

Investment percentage.

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No definition available.

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- Definition

Number Of Refineries

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No definition available.

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- Definition

Ownership interest in joint venture.

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No definition available.

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- Definition

Amount classified as assets attributable to disposal group held for sale or disposed of.

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- Definition

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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- Definition

The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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The cash inflow associated with the sale, maturity and collection of all investments such as debt, security and so forth during the period.

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- 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.

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No definition available.

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Investments - Additional Information (Detail) AUD in Millions, $ in Millions	1 Months Ended		3 Months Ended		6 Months Ended			12 Months Ended
	Apr. 30, 2016 USD ($) Refinery	Apr. 30, 2016 AUD Refinery	Jun. 30, 2016 USD ($)	Jun. 30, 2016 AUD	Jun. 30, 2016 USD ($)	Jun. 30, 2016 AUD	Jun. 30, 2015 USD ($)	Dec. 31, 2004	Dec. 31, 2015 USD ($)
Schedule of Equity Method Investments [Line Items]
Gain after tax and noncontrolling interest			$ 11	AUD 15	$ 27	AUD 35
Number of alumina refineries to be powered under supplied agreement \| Refinery	3	3
Sales of investments					275		$ 22
Carrying value of available-for-sale-securities			128		$ 128				$ 127
Alcoa Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest in joint venture	60.00%	60.00%			25.10%	25.10%
Alumina Limited of Australia [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest in joint venture	40.00%	40.00%
AofA [Member] \| Dampier to Bunbury Natural Gas Pipeline [Member]
Schedule of Equity Method Investments [Line Items]
Investment percentage in DBP to be sold	20.00%	20.00%
Amount to be received by sale of investment percentage in DBP	$ 145	AUD 192
Percentage of access to be maintained in DBNGP transmission capacity for gas supply	30.00%	30.00%						20.00%
Exchange Traded Fixed Income and Equity Securities [Member]
Schedule of Equity Method Investments [Line Items]
Sales of investments					$ 130
Loss on sale of investment					3
Loss on sale of investment, after tax					2
Carrying value of available-for-sale-securities			$ 68		$ 68				$ 193