Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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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.

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No definition available.

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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DEBT Interest Rate Swap Agreements (Details) - USD ($) $ in Millions	1 Months Ended
	Sep. 30, 2017	Aug. 31, 2017	Aug. 31, 2017	Jul. 31, 2017	Apr. 30, 2017	Mar. 31, 2017	Aug. 31, 2016	Jul. 31, 2016	Sep. 06, 2017	Aug. 16, 2017	Aug. 03, 2017	Jul. 24, 2017	Apr. 01, 2017	Mar. 01, 2017	Dec. 31, 2016	Aug. 01, 2016	Jul. 01, 2016
Derivative
Long-term debt	$ 4,263														$ 4,112
Notional amount	$ 750
Interest Rate Swap
Derivative
Notional amount									$ 75	$ 300	$ 85	$ 40	$ 50	$ 100		$ 25	$ 75
Weighted Average Fixed Rate									1.796%	1.86%	2.262%	2.2705%	2.44%	2.661%		1.599%	1.616%
Original Term	5 years	10 years	5 years	10 years	10 years	10 years	10 years	10 years
Fair Value, Inputs, Level 2 \| Recurring Basis \| Interest Rate Swap
Derivative
Interest rate swap fair value, asset	$ 11
Interest rate swaps fair value, liability	4
ITC Holdings \| Senior Notes, due January 31, 2018
Derivative
Long-term debt	$ 385
Interest rate	6.05%
ITC Holdings \| Term Loan Credit Agreement, Due March 24, 2018 [Member]
Derivative
Long-term debt	$ 200