Costs Incurred Relating to Oil and Gas Property Acquisition, Exploration and Development Activities (Detail) - USD ($)
$ in Millions |
12 Months Ended |
Jun. 30, 2021 |
Jun. 30, 2020 |
Jun. 30, 2019 |
| Costs incurred oil and gas property acquisition exploration and development activities [line items] |
|
|
|
| Acquisitions of proved property |
$ 642
|
|
|
| Acquisitions of unproved property |
19
|
$ 44
|
$ 5
|
| Exploration |
499
|
686
|
726
|
| Development |
1,134
|
1,008
|
978
|
| Total costs |
2,294
|
1,738
|
1,709
|
| Australia [member] |
|
|
|
| Costs incurred oil and gas property acquisition exploration and development activities [line items] |
|
|
|
| Exploration |
23
|
38
|
44
|
| Development |
201
|
232
|
132
|
| Total costs |
224
|
270
|
176
|
| United States [member] |
|
|
|
| Costs incurred oil and gas property acquisition exploration and development activities [line items] |
|
|
|
| Acquisitions of proved property |
642
|
|
|
| Acquisitions of unproved property |
19
|
38
|
5
|
| Exploration |
166
|
278
|
190
|
| Development |
749
|
676
|
792
|
| Total costs |
1,576
|
992
|
987
|
| Other countries [member] |
|
|
|
| Costs incurred oil and gas property acquisition exploration and development activities [line items] |
|
|
|
| Acquisitions of unproved property |
|
6
|
|
| Exploration |
310
|
370
|
492
|
| Development |
184
|
100
|
54
|
| Total costs |
$ 494
|
$ 476
|
$ 546
|