Financial liabilties designated at fair value - Narrative (Details) - Financial liabilities designated at fair value - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Disclosure of financial liabilities [line items]
Difference between carrying amount of financial liability and amount contractually required to pay at maturity to holder of obligation	$ 6,120	$ (11,496)
Accumulated increase (decrease) in fair value of financial liability, attributable to changes in credit risk of liability	2,877	209
HSBC Holdings
Disclosure of financial liabilities [line items]
Difference between carrying amount of financial liability and amount contractually required to pay at maturity to holder of obligation	2,227	920
Accumulated increase (decrease) in fair value of financial liability, attributable to changes in credit risk of liability	$ 1,386	$ 812

The accumulated increase (decrease) in the fair value of financial liabilities that is attributable to changes in the credit risk of the liabilities. [Refer: Credit risk [member]; Market risk [member]; Increase (decrease) in fair value of financial liability, attributable to changes in credit risk of liability]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 10
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_10_a&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 10A
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_10A_a&doctype=Standard
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- Definition

The amount by which the carrying amount of a financial liability is more (less) than the amount that the entity would be contractually required to pay at maturity to the holder of the obligation. [Refer: Carrying amount [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 10
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_10_b&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2018-01-01
-Paragraph 10A
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_10A_b&doctype=Standard
-URIDate 2018-03-16

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

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