The amount of total contract value.

No definition available.

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- Definition

The period over which the expansion project is designed to be phased in.

+ References

No definition available.

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- Definition

The contractual term of long term transportation capacity.

+ References

No definition available.

+ Details

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- Definition

Related Party, Contract Capacity

+ References

No definition available.

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- Definition

Related Party, Contract Value Terminated

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No definition available.

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- Definition

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

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

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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- Definition

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.

+ References

No definition available.

+ Details

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RELATED PARTY TRANSACTIONS - Narrative (Details) MMBTU / d in Thousands, $ in Millions			3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 01, 2020 USD ($)	Nov. 01, 2017	Sep. 30, 2020 USD ($) MMBTU / d	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) MMBTU / d	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Amount included in receivables from related party			$ 1		$ 1				$ 0
General Partner \| Reimbursement of costs of services provided
Related Party Transaction [Line Items]
Costs charged			1	$ 1	3	$ 3
ANR Pipeline Company \| Natural gas transmission IT application
Related Party Transaction [Line Items]
Intangible assets acquired	$ 51
Great Lakes \| TC Energy
Related Party Transaction [Line Items]
Amount included in receivables from related party			$ 12		$ 12				$ 19
Great Lakes \| TC Energy \| Transportation contracts
Related Party Transaction [Line Items]
Contract term		10 years
Contract capacity \| MMBTU / d			722		722
Great Lakes \| ANR Pipeline Company \| Transportation contracts
Related Party Transaction [Line Items]
Contract value			$ 182		$ 182		$ 1,300
Contract term					20 years		15 years
Contract value terminated								$ 1,100
Contract capacity \| MMBTU / d			168		168
Great Lakes \| Customer concentration risk \| Total net revenues \| TC Energy \| Transportation contracts
Related Party Transaction [Line Items]
Percent of total revenues			74.00%	73.00%	74.00%	73.00%
PNGTS \| Affiliates \| Portland XPress expansion project (PXP), Phase III
Related Party Transaction [Line Items]
Phase in period					3 years
TC Pipelines, LP \| ANR Pipeline Company \| Natural gas transmission IT application
Related Party Transaction [Line Items]
Intangible assets acquired	$ 38