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

No definition available.

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- Definition

Amount of revenue and income classified as other.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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REVENUES - Disaggregation of Revenues (Details) - CAD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 12,670	$ 12,794
Other revenues	585	885
Revenues	13,255	13,679	$ 13,449
Capacity arrangements and transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11,279	10,280
Power generation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	662	1,771
Natural gas storage and other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	729	743
Canadian Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4,010	4,038
Other revenues	0	0
Revenues	4,010	4,038	3,693
Canadian Natural Gas Pipelines \| Capacity arrangements and transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4,010	4,038
Canadian Natural Gas Pipelines \| Power generation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Canadian Natural Gas Pipelines \| Natural gas storage and other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
U.S. Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4,895	4,203
Other revenues	83	111
Revenues	4,978	4,314	3,584
U.S. Natural Gas Pipelines \| Capacity arrangements and transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4,245	3,549
U.S. Natural Gas Pipelines \| Power generation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
U.S. Natural Gas Pipelines \| Natural gas storage and other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	650	654
Mexico Natural Gas Pipelines
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	603	619
Other revenues	0	0
Revenues	603	619	570
Mexico Natural Gas Pipelines \| Capacity arrangements and transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	601	614
Mexico Natural Gas Pipelines \| Power generation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Mexico Natural Gas Pipelines \| Natural gas storage and other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2	5
Liquids Pipelines
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,427	2,082
Other revenues	452	502
Revenues	2,879	2,584	2,009
Liquids Pipelines \| Capacity arrangements and transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,423	2,079
Liquids Pipelines \| Power generation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Liquids Pipelines \| Natural gas storage and other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4	3
Power and Storage
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	735	1,852
Other revenues	50	272
Revenues	785	2,124	$ 3,593
Power and Storage \| Capacity arrangements and transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0	0
Power and Storage \| Power generation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	662	1,771
Power and Storage \| Natural gas storage and other
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 73	$ 81