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

Average fixed interest rate related to the group of interest rate derivatives.

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Average variable interest rate related to the group of interest rate derivatives.

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Fixed interest rate related to the interest rate derivative.

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- Definition

The effective portion of losses on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
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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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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
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-Name Accounting Standards Codification
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DEBT Interest Rate Swap Agreements (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2016	Jul. 01, 2016	Jun. 01, 2016	Mar. 31, 2016	Dec. 31, 2015
Derivative
Notional amount	$ 300.0			$ 200.0
Weighted average fixed interest rate	1.99%
Comparable reference rate	1.37%
Loss on derivative	$ 17.2
Long-term debt	3,853.7				$ 3,653.6
Tranche One
Derivative
Notional amount			$ 50.0
Fixed interest rate			1.736%
Tranche Two
Derivative
Notional amount			$ 50.0
Fixed interest rate			1.631%
ITC Holdings \| Senior Notes, due January 31, 2018
Derivative
Long-term debt	$ 384.2
Subsequent Event \| Tranche One
Derivative
Notional amount		$ 25.0
Fixed interest rate		1.584%
Subsequent Event \| Tranche Two
Derivative
Notional amount		$ 50.0
Fixed interest rate		1.632%