LONG-TERM INVESTMENTS - Summary of Combined Financial Information (Details) - CAD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income statement information
Operating revenues	$ 15,687	$ 19,217	$ 16,213
Operating expenses	13,153	15,634	13,197
Earnings	3,016	2,954	2,728
Earnings attributable to Enbridge	1,359	1,382	1,262
Balance sheet information
Current assets	2,481	3,289
Non-current assets	48,942	49,116
Current liabilities	4,047	5,536
Non-current liabilities	18,126	15,875
Noncontrolling interests	2,779	3,479
Seaway
Income statement information
Operating revenues	1,252	966	959
Operating expenses	428	212	286
Earnings	818	646	672
Earnings attributable to Enbridge	409	323	336
Balance sheet information
Current assets	107	113
Non-current assets	3,404	3,585
Current liabilities	136	123
Non-current liabilities	45	16
Noncontrolling interests	0	0
Other
Income statement information
Operating revenues	14,435	18,251	15,254
Operating expenses	12,725	15,422	12,911
Earnings	2,198	2,308	2,056
Earnings attributable to Enbridge	950	1,059	$ 926
Balance sheet information
Current assets	2,374	3,176
Non-current assets	45,538	45,531
Current liabilities	3,911	5,413
Non-current liabilities	18,081	15,859
Noncontrolling interests	$ 2,779	$ 3,479