OTHER INCOME AND EXPENSE - Other income - Sale of fixed income investments (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 COP ($)
Debt securities \| Investment securities at fair value \| Financial assets measured at fair value through other comprehensive income, category [member]
Disclosure of financial assets [line items]
Profit on sale of investment	$ 197,458

The gain on the disposal of investments.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 98
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_98_d&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_GainsOnDisposalsOfInvestments
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration