SIGNIFICANT ACCOUNTING POLICIES SIGNIFICANT ACCOUNTING POLICIES - Intangible Assets Other Than Goodwill (Details) (Details) - Private Equity	12 Months Ended
	Dec. 31, 2019
Water and sewage concession agreements [Member]
Disclosure of detailed information about intangible assets [line items]
Useful lives or amortisation rates, intangible assets other than goodwill	40
Brand names [member]
Disclosure of detailed information about intangible assets [line items]
Useful lives or amortisation rates, intangible assets other than goodwill	20
Computer software [member]
Disclosure of detailed information about intangible assets [line items]
Useful lives or amortisation rates, intangible assets other than goodwill	10
Customer-related intangible assets [member]
Disclosure of detailed information about intangible assets [line items]
Useful lives or amortisation rates, intangible assets other than goodwill	30
Value of insurance contracts acquired [Domain]
Disclosure of detailed information about intangible assets [line items]
Useful lives or amortisation rates, intangible assets other than goodwill	15
Copyrights, patents and other industrial property rights, service and operating rights [member]
Disclosure of detailed information about intangible assets [line items]
Useful lives or amortisation rates, intangible assets other than goodwill	40
Technology-based intangible assets [member]
Disclosure of detailed information about intangible assets [line items]
Useful lives or amortisation rates, intangible assets other than goodwill	20
Capitalised development expenditure [member]
Disclosure of detailed information about intangible assets [line items]
Useful lives or amortisation rates, intangible assets other than goodwill	5
Distribution networks [Member]
Disclosure of detailed information about intangible assets [line items]
Useful lives or amortisation rates, intangible assets other than goodwill	25
Loyalty program [Member]
Disclosure of detailed information about intangible assets [line items]
Useful lives or amortisation rates, intangible assets other than goodwill	15