Fair Value Measurements (Fair Value Measurements At Reporting Date) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Jun. 30, 2012	Jun. 30, 2011
Assets:
Unrealized derivative gains	$ 2,676	$ 3,063	$ 3,007
Deferred consideration	900	629
Liabilities:
Unrealized derivative losses	2,591	2,995	2,759
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Assets:
Marketable securities	2,451	1,666	1,628
Total Assets	3,877	2,941	2,826
Liabilities:
Total Liabilities	1,600	1,489	1,317
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Commodity Contracts [Member]
Assets:
Unrealized derivative gains	1,426	1,275	1,198
Liabilities:
Unrealized derivative losses	1,600	1,487	1,317
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Foreign Exchange Contracts [Member]
Liabilities:
Unrealized derivative losses		2
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Inventories carried at market	5,291	5,297	5,153
Marketable securities	16	26	328
Deferred consideration	900	629
Total Assets	7,314	7,569	7,178
Liabilities:
Inventory-related payables	903	307	278
Total Liabilities	1,756	1,634	1,649
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Commodity Contracts [Member]
Assets:
Unrealized derivative gains	936	1,397	1,457
Liabilities:
Unrealized derivative losses	638	1,038	1,193
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Foreign Exchange Contracts [Member]
Assets:
Unrealized derivative gains	170	219	237
Liabilities:
Unrealized derivative losses	215	289	178
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Other Contracts [Member]
Assets:
Unrealized derivative gains		1
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Interest Rate Contracts [Member]
Assets:
Unrealized derivative gains	1		3
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Inventories carried at market	1,745	1,462	762
Total Assets	1,888	1,633	874
Liabilities:
Inventory-related payables	33	38	45
Total Liabilities	171	217	89
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Commodity Contracts [Member]
Assets:
Unrealized derivative gains	143	171	112
Liabilities:
Unrealized derivative losses	138	179	44
Fair Value, Measurements, Recurring [Member] | Total Fair Value [Member]
Assets:
Inventories carried at market	7,036	6,759	5,915
Marketable securities	2,467	1,692	1,956
Deferred consideration	900	629
Total Assets	13,079	12,143	10,878
Liabilities:
Inventory-related payables	936	345	323
Total Liabilities	3,527	3,340	3,055
Fair Value, Measurements, Recurring [Member] | Total Fair Value [Member] | Commodity Contracts [Member]
Assets:
Unrealized derivative gains	2,505	2,843	2,767
Liabilities:
Unrealized derivative losses	2,376	2,704	2,554
Fair Value, Measurements, Recurring [Member] | Total Fair Value [Member] | Foreign Exchange Contracts [Member]
Assets:
Unrealized derivative gains	170	219	237
Liabilities:
Unrealized derivative losses	215	291	178
Fair Value, Measurements, Recurring [Member] | Total Fair Value [Member] | Other Contracts [Member]
Assets:
Unrealized derivative gains		1
Fair Value, Measurements, Recurring [Member] | Total Fair Value [Member] | Interest Rate Contracts [Member]
Assets:
Unrealized derivative gains	$ 1		$ 3