Acquisition of Businesses - Summary of Cash Flows Relating to Acquisitions (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Disclosure of consideration transferred business combinations [line items]
Cash paid on acquisition, including working capital settlement	$ 299	$ 22
Settlement of stamp duty liability	3	14
Less: cash and cash equivalents acquired	(7)	(2)
Less: working capital settlement received in year following acquisition	(3)
Net cash outflow arising on acquisitions	$ 292	$ 34

The amount of cash and cash equivalents in subsidiaries or other businesses over which control is obtained or lost. [Refer: Subsidiaries [member]; Cash and cash equivalents]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2020-01-01
-Paragraph 40
-Subparagraph c
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-URIDate 2020-01-01

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- Definition

The aggregate cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities. [Refer: Subsidiaries [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2020-01-01
-Paragraph 39
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2020-en-r&anchor=para_39&doctype=Standard
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- Definition

The fair value, at acquisition date, of cash transferred as consideration in a business combination. [Refer: Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2020-01-01
-Paragraph B64
-Subparagraph f
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2020-en-r&anchor=para_B64_f_i&doctype=Appendix&subtype=B
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Disclosure of consideration transferred business combinations.

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- Definition

The amount recognised as of the acquisition date for settlement of stamp duty liability assumed in a business combination.

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Working capital settlement received In the year of acquisition.

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