Earnings Per Share - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Dec. 31, 2018	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Earnings per share [abstract]
Effect of dilutive shares		12,000,000	13,000,000	14,000,000
Antidilutive shares		0	0	0
Number \| shares	266,000,000
Off-market buy-back program	$ 5,200		$ 5,220

The number of dilutive potential ordinary shares that relate to the assumed exercise of the entity's share options.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 33
-IssueDate 2019-01-01
-Paragraph 70
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2019-en-r&anchor=para_70_b&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_DilutiveEffectOfShareOptionsOnNumberOfOrdinaryShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration