Debt Disclosure [Abstract]
Debt Instruments [Abstract]
Schedule of Debt Instruments [Table]
Schedule of Debt Instruments [Table]
Business Segments [Axis]
Segment [Domain]
ITC Holdings Corp.
Parent Company [Member]
ITCTransmission
ITCTransmission [Member]
ITCTransmission
METC LLC
METC LLC [Member]
METC LLC [Member]
ITC Midwest LLC
ITC Midwest LLC [Member]
ITC Midwest LLC
ITC Great Plains LLC
ITC Great Plains LLC [Member]
ITC Great Plains LLC
Debt Instrument, Type [Axis]
Debt Instrument, Type [Axis]
Debt Instrument, Type [Axis]
Debt Instrument, Type [Domain]
Debt Instrument, Type [Domain]
[Domain] for Debt Instrument, Type [Axis]
Unsecured Debt
Unsecured Debt [Member]
Revolving Credit Agreement
Line of Credit [Member]
Secured Debt
Secured Debt [Member]
Debt Instrument [Axis]
Debt Instrument [Axis]
Debt Instrument, Name [Domain]
Debt Instrument, Name [Domain]
Senior Notes due July 15, 2013
Senior Notes due July 15, 2013 [Member]
Senior Notes due July 15, 2013 [Member]
Senior Notes, Series A, due September 20, 2014
Senior Notes due September 20, 2014 [Member]
Senior Notes, Series A, due September 20, 2014 [Member]
Senior Notes due September 30, 2016
Senior Notes due September 30, 2016 [Member]
Senior Notes due September 30, 2016 [Member]
Senior Notes, Series B, due September 20, 2017
Senior Notes, Series B, due September 20, 2017 [Member]
Senior Notes, Series B, due September 20, 2017 [Member]
Senior Notes due September 30, 2036
Senior Notes due September 30, 2036 [Member]
Senior Notes due September 30, 2036 [Member]
Senior Notes due January 31, 2018
Senior Notes due January 31, 2018 [Member]
Senior Notes due January 31, 2018 [Member]
Senior Notes due January 15, 2020
Senior Notes due January 15, 2020 [Member]
Senior Notes due January 15, 2020 [Member]
Term Loan Credit Agreement, due August 23, 2013
Term Loan Credit Agreement, due August 23, 2013 [Member]
Term Loan Credit Agreement Due August 23, 2013 [Member]
First Mortgage Bonds, Series A, due July 15, 2013
First Mortgage Bonds due July 15, 2013 [Member]
First Mortgage Bonds, Series A, due July 15, 2013 [Member]
First Mortgage Bonds, Series C, due March 31, 2036
First Mortgage Bonds, Series C, due March 31, 2036 [Member]
First Mortgage Bonds, Series C, due March 31, 2036 [Member]
First Mortgage Bonds, Series D, due April 1, 2018
First Mortgage Bonds, Series D, due April 1, 2018 [Member]
First Mortgage Bonds, Series D, due April 1, 2018 [Member]
Senior Secured Notes due December 10, 2015
Senior Secured Notes due December 10, 2015 [Member]
Senior Secured Notes due December 10, 2015 [Member]
Senior Secured Notes due December 18, 2014
Senior Secured Notes due December 18, 2014 [Member]
Senior Secured Notes due December 18, 2014 [Member]
Senior Secured Notes due May 6, 2040
Senior Secured Notes due May 6, 2040 [Member]
Senior Secured Notes due May 6, 2040 [Member]
Senior Secured Notes, due October 26, 2042
Senior Secured Notes, due October 26, 2042 [Member]
Senior Secured Notes, due October 26, 2042 [Member]
First Mortgage Bonds, Series A, due January 31, 2038
First Mortgage Bonds due January 31, 2038 [Member]
First Mortgage Bonds, Series A, due January 31, 2038 [Member]
First Mortgage Bonds, Series B, due December 22, 2017
First Mortgage Bonds, Series B, due December 22, 2017 [Member]
First Mortgage Bonds, Series B, due December 22, 2017 [Member]
First Mortgage Bonds, Series C, due December 22, 2020
First Mortgage Bonds, Series C, due December 22, 2020 [Member]
First Mortgage Bonds, Series C, due December 22, 2020 [Member]
First Mortgage Bonds, Series D, due December 17, 2024
First Mortgage Bonds, Series D, due December 17, 2024 [Member]
First Mortgage Bonds, Series D, due December 17, 2024 [Member]
First Mortgage Bonds, Series E, due January 19, 2027
First Mortgage Bonds, Series E, due January 19, 2027 [Member]
First Mortgage Bonds, Series E, due January 19, 2027 [Member]
2008 Revolving Credit Agreement due January 29, 2013
2008 Revolving Credit Agreement due January 29, 2013 [Member]
2008 Revolving Credit Agreement due January 29, 2013 [Member]
2011 Revolving Credit Agreement due February 11, 2013
2011 Revolving Credit Agreement due February 11, 2013 [Member]
2011 Revolving Credit Agreement due February 11, 2013 [Member]
Debt Instrument
Debt Instrument [Line Items]
Amount outstanding
Long-term Debt
Short-term debt
Short-term Debt
Interest rate
Debt Instrument, Interest Rate, Stated Percentage
Unamortized discount
Debt Instrument, Unamortized Discount
Debt maturing within one year
Long-term Debt, Current Maturities
Income Statement [Abstract]
Statement [Table]
Statement [Table]
Legal Entity [Axis]
Legal Entity [Axis]
Entity [Domain]
Entity [Domain]
Statement [Line Items]
Statement [Line Items]
OPERATING REVENUES
Electric Revenue
OPERATING EXPENSES
Operating Expenses [Abstract]
Operation and maintenance
Cost of Goods Sold, Electric
General and administrative
General and Administrative Expense
Depreciation and amortization
Depreciation, Depletion and Amortization, Nonproduction
Taxes other than income taxes
Taxes, Other
Other operating (income) expense - net
Other Operating Income (Expense), Net
Total operating expenses
Costs and Expenses
OPERATING INCOME
Operating Income (Loss)
OTHER EXPENSES (INCOME)
Nonoperating Income (Expense) [Abstract]
Interest expense
Interest Expense
Allowance for equity funds used during construction
Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity
Other income
Other Nonoperating Income
Other expense
Other Nonoperating Expense
Total other expenses (income)
Nonoperating Income (Expense)
INCOME BEFORE INCOME TAXES
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest
INCOME TAX PROVISION
Income Tax Expense (Benefit)
NET INCOME
Net Income (Loss) Attributable to Parent
Basic earnings per common share
Earnings Per Share, Basic
Diluted earnings per common share
Earnings Per Share, Diluted
Dividends declared per common share
Common Stock, Dividends, Per Share, Declared
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
FERC approved capital structure, equity percentage
FERC Approved Capital Structure, Equity Percentage
FERC Approved Capital Structure, Equity Percentage
FERC approved capital structure, debt percentage
FERC Approved Capital Structure, Debt Percentage
FERC Approved Capital Structure, Debt Percentage
Accounting Policies [Abstract]
Accounts Receivable
Receivables [Abstract]
Accounts receivable reserve
Allowance for Doubtful Accounts Receivable
Property, Plant and Equipment
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense
Depreciation, Depletion and Amortization
Composite depreciation rate
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service
AFUDC debt
Allowance for Funds Used During Construction, Capitalized Interest
Schedule of Property, Plant and Equipment [Table]
Schedule of Property, Plant and Equipment [Table]
Range [Axis]
Range [Axis]
Range [Domain]
Range [Domain]
Minimum
Minimum [Member]
Maximum
Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life
Property, Plant and Equipment, Useful Life
Goodwill and Intangible Assets
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment
Goodwill, Impairment Loss
Deferred Financing Fees and Discount or Premium on Debt
Deferred Financing Fees and Discount or Premium on Debt [Abstract]
Deferred Financing Fees and Discount or Premium on Debt [Abstract]
Amortization of deferred financing fees and debt discounts
Amortization of Financing Costs and Discounts
Asset Retirement Obligations
Asset Retirement Obligation [Abstract]
Asset retirement obligations
Asset Retirement Obligations, Noncurrent
Compensation and Retirement Disclosure [Abstract]
Schedule of Defined Benefit Plans Disclosures [Table]
Defined Benefit Plans and Other Postretirement Benefit Plans [Axis]
Defined Benefit Plans and Other Postretirement Benefit Plans [Domain]
Retirement Plan
Pension Plans, Defined Benefit [Member]
Other Postretirement Benefits Plan
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan Assets By Category
Schedule of Plan Assets By Category [Table Text Block]
Schedule of Plan Assets By Category [Table Text Block]
Net Defined Benefit Cost Components
Schedule of Net Benefit Costs [Table Text Block]
Defined Benefit Plans Disclosures
Schedule of Defined Benefit Plans Disclosures [Table Text Block]
Assumptions Used
Schedule of Assumptions Used [Table Text Block]
Projected Benefit Payments
Schedule of Expected Benefit Payments [Table Text Block]
Assets Measured at Fair Value Subject to Three-Tier Hierarchy
Schedule of Allocation of Plan Assets [Table Text Block]
Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates
Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block]
Schedule of Condensed Financial Statements [Table]
Schedule of Condensed Financial Statements [Table]
Condensed Financial Statements, Captions
Condensed Financial Statements, Captions [Line Items]
Maturities of Long-term Debt [Abstract]
Maturities of Long-term Debt [Abstract]
2013
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months
2014
Long-term Debt, Maturities, Repayments of Principal in Year Two
2015
Long-term Debt, Maturities, Repayments of Principal in Year Three
2016
Long-term Debt, Maturities, Repayments of Principal in Year Four
2017
Long-term Debt, Maturities, Repayments of Principal in Year Five
2018 and thereafter
Long-term Debt, Maturities, Repayments of Principal after Year Five
Total
Long-term Debt, Gross
Fair Value Disclosures [Abstract]
Fair Value Disclosures [Abstract]
Fair value of long-term debt, excluding revolving and term loan credit agreements
Long-term Debt, Fair Value
Book value of long-term debt, excluding revolving and term loan credit agreements
Book value of revolving and term loan credit agreements
Line of Credit Facilities and Other Debt, Total Amount Outstanding
Line of Credit Facilities and Other Debt, Total Amount Outstanding
Segment Reporting [Abstract]
Financial Information by Reportable Segment
Schedule of Segment Reporting Information, by Segment [Table Text Block]
Assets Measured at Fair Value Subject to Three-Tier Hierarchy
Fair Value, Assets Measured on Recurring Basis [Table Text Block]
Principles of Consolidation
Consolidation, Policy [Policy Text Block]
Use of Estimates
Use of Estimates, Policy [Policy Text Block]
Regulation
Public Utilities, Policy [Policy Text Block]
Cash and Cash Equivalents
Cash and Cash Equivalents, Policy [Policy Text Block]
Accounts Receivables
Receivables, Policy [Policy Text Block]
Inventories
Inventory, Policy [Policy Text Block]
Property, Plant and Equipment
Property, Plant and Equipment, Policy [Policy Text Block]
Impairment of Long-Lived Assets
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]
Goodwill and Intangible Assets
Goodwill and Intangible Assets, Policy [Policy Text Block]
Deferred Financing Fees and Discount or Premium On Debt
Deferred Financing Fees and Discount or Premium On Debt, Policy [Policy Text Block]
Deferred Financing Fees and Discount or Premium On Debt, Policy [Policy Text Block]
Asset Retirement Obligations
Asset Retirement Obligations, Policy [Policy Text Block]
Financial Instruments
Derivatives, Policy [Policy Text Block]
Contingent Obligations
Commitments and Contingencies, Policy [Policy Text Block]
General Interconnection Projects
General Interconnection Projects, Policy [Policy Text Block]
General Interconnection Projects, Policy [Policy Text Block]
Revenues
Revenue Recognition, Policy [Policy Text Block]
Share-Based Payment
Compensation Related Costs, Policy [Policy Text Block]
Comprehensive Income (Loss)
Comprehensive Income, Policy [Policy Text Block]
Income Taxes
Income Tax, Policy [Policy Text Block]
Line of Credit Facility [Abstract]
Line of Credit Facility [Table]
Line of Credit Facility [Table]
Segment [Domain]
Line of Credit Facility
Line of Credit Facility [Line Items]
Total available capacity
Line of Credit Facility, Current Borrowing Capacity
Outstanding balance
Line of Credit Facility, Amount Outstanding
Unused capacity
Line of Credit Facility, Remaining Borrowing Capacity
Weighted-average interest rate
Debt, Weighted Average Interest Rate
Commitment fee rate
Line of Credit Facility, Commitment Fee Percentage
Original term
Line of Credit Facility, Original Term
Line of Credit Facility, Original Term
RETIREMENT BENEFITS AND ASSETS HELD IN TRUST
Pension and Other Postretirement Benefits Disclosure [Text Block]
RECENT ACCOUNTING PRONOUNCEMENTS [Abstract]
RECENT ACCOUNTING PRONOUNCEMENTS [Abstract]
RECENT ACCOUNTING PRONOUNCEMENTS
Recent Accounting Pronouncements
Recent Accounting Pronouncements [Text Block]
Regulated Operations [Abstract]
REGULATORY MATTERS
Public Utilities Disclosure [Text Block]
Schedule of Defined Benefit Plans Disclosures [Table]
Name Of Rollforward [Axis]
Name Of Rollforward [Axis]
Name Of Rollforward [Axis]
Name Of Rollforward [Domain]
Name Of Rollforward [Domain]
[Domain] for Name Of Rollforward [Axis]
Change in Benefit Obligation
Change in Benefit Obligation [Member]
Change in Benefit Obligation [Member]
Change in Plan Assets
Change in Plan Assets [Member]
Change in Plan Assets [Member]
Retirement Benefits Disclosures [Axis]
Retirement Benefits Disclosures [Axis]
Retirement Benefits Disclosures [Axis]
Retirement Benefits [Domain]
Retirement Benefits [Domain]
Retirement Benefits [Domain]
Supplemental Retirement Benefit Plans
Supplemental Employee Retirement Plans, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Axis]
Defined Benefit Plans and Other Postretirement Benefit Plans [Domain]
Defined Benefit Plan Disclosure
Defined Benefit Plan Disclosure [Line Items]
Change in Benefit Obligation:
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning obligation
Defined Benefit Plan, Benefit Obligation
Service cost
Defined Benefit Plan, Service Cost
Interest cost
Defined Benefit Plan, Interest Cost
Actuarial net loss
Defined Benefit Plan, Actuarial Gain (Loss)
Benefits paid
Defined Benefit Plan, Benefits Paid
Ending obligation
Change in Plans' Assets:
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning plan assets at fair value
Defined Benefit Plan, Fair Value of Plan Assets
Actual return on plan assets
Defined Benefit Plan, Actual Return on Plan Assets
Employer contributions
Defined Benefit Plan, Contributions by Employer
Employer provided retiree premiums
Defined Benefit Plan, Contributions By Employer For Retiree Insurance Premiums
Defined Benefit Plan, Contributions By Employer For Retiree Insurance Premiums
Ending plan assets at fair value
Funded status, underfunded
Defined Benefit Plan, Funded Status of Plan
Ending accumulated benefit obligation
Defined Benefit Plan, Accumulated Benefit Obligation
Funded Status:
Defined Benefit Plan, Plans with Benefit Obligations in Excess of Plan Assets [Abstract]
Accrued liabilities
Pension and Other Postretirement Defined Benefit Plans, Liabilities
Pension assets - other assets - other
Defined Benefit Plan, Assets for Plan Benefits
Total
Defined Benefit Plan, Amounts Recognized in Balance Sheet
Unrecognized Amounts in Other Regulatory Assets:
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax [Abstract]
Net actuarial loss
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax
Prior service credit
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax
Total
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax
Statement of Stockholders' Equity [Abstract]
Statement, Equity Components [Axis]
Equity Components [Axis]
Equity Component [Domain]
Equity Component [Domain]
Common Stock
Common Stock [Member]
Retained Earnings
Retained Earnings [Member]
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Member]
Total Stockholders' Equity
Parent [Member]
Stockholders' equity
Stockholders' Equity Attributable to Parent
Common stock, shares
Common Stock, Shares, Outstanding
NET INCOME
Repurchase and retirement of common stock
Stock Repurchased and Retired During Period, Value
Repurchase and retirement of common stock, shares
Stock Repurchased and Retired During Period, Shares
Dividends declared on common stock
Dividends, Common Stock
Stock option exercises
Stock Issued During Period, Value, Stock Options Exercised
Stock option exercises, shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period
Shares issued under the Employee Stock Purchase Plan
Stock Issued During Period, Value, Employee Stock Purchase Plan
Shares issued under the Employee Stock Purchase Plan, shares
Stock Issued During Period, Shares, Employee Stock Purchase Plans
Issuance of restricted stock
Stock Issued During Period, Shares, Restricted Stock Award, Gross
Forfeiture of restricted stock
Stock Issued During Period, Value, Restricted Stock Award, Forfeitures
Forfeiture of restricted stock, shares
Stock Issued During Period, Shares, Restricted Stock Award, Forfeited
Vesting of deferred stock units
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures
Share-based compensation, net of forfeitures
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition
Amortization of interest rate lock cash flow hedges
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax
Unrealized (loss) gain on interest rate swaps relating to interest rate cash flow hedges
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax
Tax benefit for excess tax deductions of share-based compensation
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation
Other
Stockholders' Equity, Other
Stockholders' equity
Common stock, shares
Regulatory Assets and Liabilities Disclosure [Abstract]
Schedule of Regulatory Assets and Liabilities
Schedule of Regulatory Assets and Liabilities [Table]
Schedule of Regulatory Assets and Liabilities [Table]
Statement, Business Segments [Axis]
Regulatory Asset [Axis]
Regulatory Asset [Axis]
Regulatory Asset [Domain]
Regulatory Asset [Domain]
Start-up and Development, Including the KETA Project and the Kansas V-Plan Project Prior to Construction
Start-up and Development, Including the KETA Project and the Kansas V-Plan Project Prior to Construction [Member]
Start-up and Development Costs, Including Certain Costs Incurred for the KETA Project and the Kansas V-Plan Project Prior to Construction [Member]
Kansas V-Plan
Kansas V-Plan [Member]
Kansas V-Plan
Rate Discount [Axis]
Rate Discount [Axis]
Rate Discount [Domain]
Rate Discount [Domain]
Rate Discount
Rate Discount [Member]
Rate Discount [Member]
Rate Freeze Revenue Deferral [Axis]
Rate Freeze Revenue Deferral [Axis]
Rate Freeze Revenue Deferral [Domain]
Rate Freeze Revenue Deferral [Domain]
Rate Freeze Revenue Deferral
Rate Freeze Revenue Deferral [Member]
Rate Freeze Revenue Deferral [Member]
Change in Accounting Estimate by Type [Axis]
Change in Accounting Estimate by Type [Axis]
Change in Accounting Estimate, Type [Domain]
Change in Accounting Estimate, Type [Domain]
Depreciable Assets
Depreciable Assets [Member]
Regulatory Assets and Liabilities
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets and Liabilities [Line Items]
Regulatory asset
Regulatory Assets
Decrease in operating expenses
Decrease in Operating Expenses
Decrease in Operating Expenses
Increase in net income
Increase in Net Income
Increase in Net Income
Regulatory asset, amortization period (in years)
Regulatory Noncurrent Asset, Amortization Period
Transmission rate, applicable period
Transmission Rate, Applicable Period
Transmission Rate, Applicable Period
Revenue true-up amount reflected in customer bill, period of recognition
Revenue True-up Amount Reflected In Customer Bill, Period of Recognition
The time period from the time the true-up amount is calculated from revenue accruals and deferrals based on revenue requirements to the time the true-up amount is reflected in customer bills.
Rate discount
Rate discount
Rate discount
Rate discount period
Rate Discount Period
Rate Discount Period
Amortization period
Revenue Rate Freeze, Amortization Period
Revenue Rate Freeze, Amortization Period
Revenue from rate freeze
Revenue From Rate Freeze Revenue Deferral
Revenue From Rate Freeze Revenue Deferral
Other income
General and administrative expense
Interest expense
Other expense
Income tax provision (benefit)
LOSS AFTER TAXES
Income (Loss) Attributable to Parent
EQUITY IN SUBSIDIARIES’ NET EARNINGS
Equity in Subsidiaries' Net Earnings
Equity in Subsidiaries' Net Earnings
Defined Benefit Plan, Assumption Category [Axis]
Defined Benefit Plan, Assumption Category [Axis]
Defined Benefit Plan, Assumption Category [Axis]
Defined Benefit Plan, Assumption Category [Domain]
Defined Benefit Plan, Assumption Category [Domain]
Defined Benefit Plan, Assumption Category [Domain]
Benefit Obligation
Defined Benefit Plan, Benefit Obligation [Member]
Defined Benefit Plan, Benefit Obligation [Member]
Benefit Cost
Defined Benefit Plan, Benefit Cost [Member]
Defined Benefit Plan, Benefit Cost [Member]
Benefit Obligation Assumptions
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate
Annual rate of salary increases
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase
Benefit Cost Assumptions
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate
Annual rate of salary increases
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase
Expected long-term rate of return on plan assets
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets
Assumed Health Care Cost Trend Rates
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Health care cost trend rate assumed for next year
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year
Rate to which the cost trend rate is assumed to decline
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate
Year that the rate reaches the ultimate trend rate
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate
Annual rate of increase in dental benefit costs
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Annual Rate Of Increase In Dental Benefit Costs
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Annual Rate Of Increase In Dental Benefit Costs
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]
Award Type
Award Type [Axis]
Award Type
Award Type [Domain]
Stock Options
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value per option
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value
Expected volatility
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate
Risk-free interest rate
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term, Simplified Method
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term, Simplified Method
Expected term
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term
Expected dividend yield
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate
Estimated fair value of underlying shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Estimated Fair Value of Underlying Shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Estimated Fair Value of Underlying Shares
Selected Quarterly Financial Information [Abstract]
Operating revenues
Operating income
Basic earnings per share
Diluted earnings per share
Schedule of Anticipated Business Mergers, by Merger [Table]
Schedule of Anticipated Business Mergers, by Merger [Table]
ITC Holdings Corp.
ITC Holdings Corp. [Member]
ITC Holdings Corp. [Member]
Internal Labor and Related Costs
Component of Other Operating Cost and Expense [Axis]
Component of Other Operating Cost and Expense, Name [Domain]
Component of Other Operating Cost and Expense, Name [Domain]
External Legal, Advisory and Financial Services Fees
Professional Fees [Member]
Internal Labor and Related Costs
Internal Labor and Related Costs [Member]
Internal Labor and Related Costs [Member]
Entergy Transaction
Anticipated Business Merger [Line Items]
Anticipated Business Merger [Line Items]
Transaction related expenses
Business Combination, Acquisition Related Costs
Schedule of Debt
Schedule of Debt [Table Text Block]
Schedule of Maturities of Debt
Schedule of Maturities of Long-term Debt [Table Text Block]
Schedule of Interest Rate Swap Agreements
Schedule of Interest Rate Derivatives [Table Text Block]
Schedule of Revolving Credit Agreements
Schedule of Line of Credit Facilities [Table Text Block]
Business Combinations [Abstract]
ENTERGY TRANSACTION
Anticipated Merger Disclosures [Text Block]
Anticipated Merger Disclosures [Text Block]
Income Tax Disclosure [Abstract]
Schedule of Deferred Tax Assets and Liabilities [Table]
Schedule of Deferred Tax Assets and Liabilities [Table]
Schedule of Deferred Tax Assets and Liabilities [Table]
Income Tax Authority [Axis]
Income Tax Authority [Axis]
Income Tax Authority [Domain]
Income Tax Authority [Domain]
Federal Tax Jurisdiction
Internal Revenue Service (IRS) [Member]
Statement, Business Segments [Axis]
Deferred Tax Assets and Liabilities, Type [Axis]
Deferred Tax Assets and Liabilities, Type [Axis]
Deferred Tax Assets and Liabilities, Type [Axis]
Deferred Tax Assets and Liabilities, Type [Domain]
Deferred Tax Assets and Liabilities, Type [Domain]
Deferred Tax Assets and Liabilities, Type [Domain]
Revenue Deferrals, Including Accrued Interest
Revenue Deferrals, Including Accrued Interest [Member]
Revenue Deferrals, Including Accrued Interest [Member]
ADIT Deferral
ADIT Deferral [Member]
ADIT Deferral [Member]
Revenue Accruals/Deferrals - Net (Including Accrued Interest)
Revenue Accruals Deferrals Net Including Accrued Interest [Member]
Revenue Accruals/Deferrals - Net (Including Accrued Interest) [Member]
Deferred Tax Assets and Liabilities
Deferred Tax Assets and Liabilities [Line Items]
Deferred Tax Assets and Liabilities [Line Items]
Property, plant and equipment
Deferred Tax Liabilities, Property, Plant and Equipment
Deferred tax liabilities, regulatory assets
Deferred Tax Liabilities, Regulatory Assets
Goodwill
Deferred Tax Liabilities, Goodwill
Revenue accruals/deferrals - net (including accrued interest)
Deferred Tax Assets, Regulatory Assets and Liabilities
Pension and postretirement liabilities
Deferred Tax Assets, Deferred Expense, Compensation and Benefits, Pension and Postretirement Benefits
Deferred Tax Assets, Deferred Expense, Compensation and Benefits, Pension and Postretirement Benefits
State income tax NOLs (net of federal benefit)
Deferred Tax Assets, Operating Loss Carryforwards, State and Local
Share-based compensation
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost
Other - net
Deferred Tax Liabilities, Other
Net deferred tax liabilities
Deferred Tax Assets, Net
Gross deferred income tax liabilities
Deferred Tax Liabilities, Gross
Gross deferred income tax assets
Deferred Tax Assets, Gross
Organization, Consolidation and Presentation of Financial Statements [Abstract]
GENERAL
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]
MTH
MTH [Member]
MTH [Member]
Dividends from subsidiaries
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries
Return of capital from subsidiaries
Proceeds from Equity Method Investment, Dividends or Distributions, Return of Capital
Tax payments from subsidiary under intercompany tax sharing agreement
Tax Payments From Subsidiary Under Intercompany Tax Sharing Agreement
Tax Payments From Subsidiary Under Intercompany Tax Sharing Agreement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Table]
Fair Value Measurements, Recurring and Nonrecurring [Table]
Fair Value by Measurement Frequency [Axis]
Measurement Frequency [Axis]
Fair Value, Measurement Frequency [Domain]
Fair Value, Measurement Frequency [Domain]
Financial Assets Measured on a Recurring Basis
Fair Value, Measurements, Recurring [Member]
Fair Value, Hierarchy [Axis]
Fair Value, Measurements, Fair Value Hierarchy [Domain]
Fair Value Measurements at Reporting Date Using Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Inputs, Level 1 [Member]
Fair Value Measurements at Reporting Date Using Significant Other Observable Inputs (Level 2)
Fair Value, Inputs, Level 2 [Member]
Fair Value, Option, Quantitative Disclosures, by Eligible Item or Group [Axis]
Eligible Item or Group for Fair Value Option [Axis]
Fair Value, Option, Eligible Item or Group [Domain]
Fair Value, Option, Eligible Item or Group [Domain]
Cash Equivalents
Cash Equivalents [Member]
Fixed Income Securities
Fixed Income Securities [Member]
Equity Securities
Equity Securities [Member]
Interest Rate Swap
Interest Rate Swap [Member]
Fair Value, Assets and Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents - cash equivalents
Cash and Cash Equivalents, Fair Value Disclosure
Mutual funds
Investments, Fair Value Disclosure
Interest rate swap derivatives - asset
Derivative Assets
Interest rate swap derivatives - liability
Derivative Financial Instruments, Liabilities, Fair Value Disclosure
Total
Assets, Fair Value Disclosure
Schedule of Goodwill and Intangible Assets [Table]
Schedule of Goodwill and Intangible Assets [Table]
Goodwill and Intangible Assets [Axis]
Goodwill and Intangible Assets [Axis]
Goodwill and Intangible Assets, Name [Domain]
Goodwill and Intangible Assets, Name [Domain]
Regulatory Deferrals
Regulatory Deferrals [Member]
Regulatory Deferrals [Member]
Goodwill and Intangible Assets
Goodwill and Intangible Assets [Line Items]
Goodwill and Intangible Assets [Line Items]
Goodwill
Goodwill
Intangible assets
Finite-Lived Intangible Assets, Net
Accumulated amortization
Finite-Lived Intangible Assets, Accumulated Amortization
Amortization period
Finite-Lived Intangible Assets, Amortization Period
Finite-Lived Intangible Assets, Amortization Period
Amortization expense
Amortization of Intangible Assets
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities [Table]
Commitments and Contingent Liabilities [Table]
Commitments and Contingent Liabilities [Table]
Audit, By Name [Axis]
Audit, By Name [Axis]
Audit, By Name [Axis]
Audit, By Name [Domain]
Audit, By Name [Domain]
Audit, By Name [Domain]
Sales and Use Tax Audit
Sales and Use Tax Audit [Member]
Sales and Use Tax Audit [Member]
FERC Audit
FERC Audit [Member]
FERC Audit [Member]
IRS Audit Period
Audit Period [Member]
Audit Period
Concentration Risk by Type [Axis]
Concentration Risk Type [Axis]
Concentration Risk Type [Domain]
Concentration Risk Type [Domain]
Customer Concentration Risk
Customer Concentration Risk [Member]
Major Customers [Axis]
Major Customers [Axis]
Name of Major Customer [Domain]
Name of Major Customer [Domain]
Detroit Edison
Detroit Edison [Member]
Detroit Edison [Member]
Consumers Energy
Consumers Energy [Member]
Consumers Energy [Member]
IP&L
Interstate Power and Light Company [Member]
Interstate Power and Light Company [Member]
Commitments and Contingent Liabilities
Commitments and Contingent Liabilities [Line Items]
Commitments and Contingent Liabilities [Line Items]
Use tax liability associated with exemptions taken
Income Tax Examination, Range of Possible Losses
Estimated liability for refund and related interest
Estimated Liability for Refund and Related Interest
Estimated Liability for Refund and Related Interest
Decrease in AFUDC debt and AFUDC equity
Decrease in AFUDC Debt and AFUDC Equity
Decrease in AFUDC Debt and AFUDC Equity
Decrease in revenue
Decrease in Revenue
Decrease in Revenue
Decrease in AFUDC equity
Decrease in AFUDC Equity
Reduction in Allowance for Equity Funds Used During Construction
Increase in interest expense
Increase in Interest Expense
Increase in Interest Expense
Decrease in net income
Decrease in Net Income
Decrease in Net Income
Purchase obligations
Unrecorded Unconditional Purchase Obligation
Rent expense
Operating Leases, Rent Expense
Future Minimum Lease Payments
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2013
Operating Leases, Future Minimum Payments Due, Next Twelve Months
2014
Operating Leases, Future Minimum Payments, Due in Two Years
2015
Operating Leases, Future Minimum Payments, Due in Three Years
2016
Operating Leases, Future Minimum Payments, Due in Four Years
2017 and thereafter
Operating Leases, Future Minimum Payments, Due Thereafter
Total minimum lease payments
Operating Leases, Future Minimum Payments Due
Concentration percentage
Concentration Risk, Percentage
Major customer revenue
Entity-Wide Revenue, Major Customer, Amount
Earnings Per Share, Basic and Diluted [Abstract]
Computation of Basic and Diluted Earnings Per Common Share
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
Income Tax Reconciliation
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]
Components of Income Tax Provision
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]
Deferred Tax Assets and Liabilities
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]
FAIR VALUE MEASUREMENTS
Fair Value Disclosures [Text Block]
ASSETS
Assets [Abstract]
Current assets
Assets, Current [Abstract]
Prepaid assets
Prepaid Expense, Current
Cash and cash equivalents
Cash and Cash Equivalents, at Carrying Value
Accounts receivable from subsidiaries
Accounts Receivable, Related Parties, Current
Other
Other Assets, Current
Total current assets
Assets, Current
Other assets
Other Assets [Abstract]
Investment in subsidiaries
Equity Method Investments
Deferred income taxes
Deferred Tax Assets, Net, Noncurrent
Deferred financing fees (net of accumulated amortization of $8,063 and $6,590, respectively)
Deferred Finance Costs, Noncurrent, Net
Other
Other Assets, Noncurrent
Total other assets
Assets, Noncurrent
TOTAL ASSETS
Assets
LIABILITIES AND STOCKHOLDERS' EQUITY
Liabilities and Equity [Abstract]
Current liabilities
Liabilities, Current [Abstract]
Accounts payable
Accounts Payable, Current
Accrued payroll
Employee-related Liabilities, Current
Accrued interest
Interest Payable, Current
Derivative instruments
Derivative Liabilities, Current
Other
Other Liabilities, Current
Total current liabilities
Liabilities, Current
Accrued pension and postretirement liabilities
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent
Derivative instruments
Derivative Liabilities, Noncurrent
Other
Other Liabilities, Noncurrent
Long-term debt (net of discounts of $1,916 and $2,401, respectively)
Long-term Debt, Excluding Current Maturities
STOCKHOLDERS' EQUITY
Stockholders' Equity Attributable to Parent [Abstract]
Common stock, without par value, 100,000,000 shares authorized, 52,248,514 and 51,323,368 shares issued and outstanding at December 31, 2012 and 2011, respectively
Common Stock, Value, Issued
Retained earnings
Retained Earnings (Accumulated Deficit)
Accumulated other comprehensive loss
Accumulated Other Comprehensive Income (Loss), Net of Tax
Total stockholders' equity
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY
Liabilities and Equity
Balance Sheet Additional Disclosures
Balance Sheet Related Disclosures [Abstract]
Deferred financing fees, accumulated amortization
Accumulated Amortization of Noncurrent Deferred Finance Costs
Common stock, without par value
Common Stock, No Par Value
Common stock, shares authorized
Common Stock, Shares Authorized
Common stock, shares issued
Common Stock, Shares, Issued
Common stock, shares outstanding
SIGNIFICANT ACCOUNTING POLICIES
Significant Accounting Policies [Text Block]
OTHER COMPREHENSIVE (LOSS) INCOME
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Amortization of interest rate lock cash flow hedges (net of tax of $31, $1 and $34 for the years ended December 31, 2012, 2011 and 2010, respectively)
Unrealized (loss) gain on interest rate swaps relating to interest rate cash flow hedges (net of tax of $1,777, $10,705 and $1,211 for the years ended December 31, 2012, 2011 and 2010, respectively)
TOTAL OTHER COMPREHENSIVE (LOSS) INCOME, NET OF TAX
Other Comprehensive Income (Loss), Net of Tax
TOTAL COMPREHENSIVE INCOME
Comprehensive Income (Loss), Net of Tax, Attributable to Parent
Statement of Other Comprehensive Income [Abstract]
Statement of Other Comprehensive Income [Abstract]
Amortization of interest rate lock cash flow hedges, tax
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Tax
Unrealized (loss) gain on interest rate swaps relating to interest rate cash flow hedges, tax
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax
CASH FLOWS FROM OPERATING ACTIVITIES
Net Cash Provided by (Used in) Operating Activities [Abstract]
Adjustments to reconcile net income to net cash provided by operating activities:
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Equity in subsidiaries’ earnings
Deferred income tax expense
Deferred Income Tax Expense (Benefit)
Intercompany tax payments from subsidiaries
Proceeds from Subsidiaries Related to Tax
Proceeds from Subsidiaries Related to Tax
Share-based compensation expense
Share-based Compensation
Other
Other Noncash Expense
Changes in assets and liabilities, exclusive of changes shown separately:
Increase (Decrease) in Operating Capital [Abstract]
Accounts receivable from subsidiaries
Increase (Decrease) in Accounts Receivable, Related Parties
Prepaid and other current assets
Increase (Decrease) in Prepaid Expense and Other Assets
Accounts payable
Increase (Decrease) in Accounts Payable
Accrued payroll
Increase (Decrease) in Employee Related Liabilities
Accrued interest
Increase (Decrease) in Interest Payable, Net
Tax benefit for excess tax deductions of share-based compensation
Excess Tax Benefit (Tax Deficiency) from Share-based Compensation, Operating Activities
Other current liabilities
Increase (Decrease) in Other Current Liabilities
Other non-current assets and liabilities, net
Increase (Decrease) in Other Noncurrent Assets and Liabilities, Net
Net cash provided by operating activities
Net Cash Provided by (Used in) Operating Activities
CASH FLOWS FROM INVESTING ACTIVITIES
Net Cash Provided by (Used in) Investing Activities [Abstract]
Equity contribution to subsidiaries
Payments to Acquire Interest in Subsidiaries and Affiliates
Proceeds from sale of securities
Proceeds from Sale and Maturity of Marketable Securities
Net cash used in investing activities
Net Cash Provided by (Used in) Investing Activities
CASH FLOWS FROM FINANCING ACTIVITIES
Net Cash Provided by (Used in) Financing Activities [Abstract]
Borrowings under revolving credit agreement
Proceeds from Lines of Credit
Borrowings under term loan credit agreement
Proceeds from Short-term Debt
Repayments of revolving credit agreement
Repayments of Lines of Credit
Issuance of common stock
Proceeds from Issuance of Common Stock
Dividends on common stock
Payments of Ordinary Dividends, Common Stock
Tax benefit for excess tax deductions of share-based compensation
Excess Tax Benefit (Tax Deficiency) from Share-based Compensation, Financing Activities
Other
Proceeds from (Payments for) Other Financing Activities
Net cash provided by (used in) financing activities
Net Cash Provided by (Used in) Financing Activities
NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS
Cash and Cash Equivalents, Period Increase (Decrease)
CASH AND CASH EQUIVALENTS - Beginning of period
CASH AND CASH EQUIVALENTS - End of period
Supplementary cash flows information:
Supplemental Cash Flow Information [Abstract]
Interest paid
Interest Paid, Net
Income taxes paid
Income Taxes Paid
Supplementary non-cash investing and financing activities:
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Equity transfers to subsidiaries
Equity Transfers to Subsidiaries, Non-Cash
Equity Transfers to Subsidiaries, Non-Cash
Schedule of Supplementary Quarterly Financial Information (Unaudited)
Schedule of Quarterly Financial Information [Table Text Block]
Jointly Owned Utility Plant Interests [Table]
Jointly Owned Utility Plant Interests [Table]
Jointly Owned Utility Plant [Axis]
Jointly Owned Utility Plant [Axis]
Jointly Owned Utility Plant [Domain]
Jointly Owned Utility Plant [Domain]
Jointly Owned Electricity Transmission and Distribution System [Member]
Transmission Substations
Jointly Owned Electricity Transmission System - Substations [Member]
Jointly Owned Electricity Transmission System - Substations [Member]
Transmission Lines
Jointly Owned Electricity Transmission System – Lines [Member]
Jointly Owned Electricity Transmission System – Lines [Member]
Jointly Owned Utility Plant Interests
Jointly Owned Utility Plant Interests [Line Items]
Net investment
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service
Construction work in progress
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress
Stock options outstanding
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number
Anti-dilutive securities excluded from calculation of earnings per share
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount
Statement of Financial Position [Abstract]
Property, plant and equipment, accumulated depreciation and amortization
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment
Intangible assets, accumulated amortization
SEGMENT INFORMATION
Segment Reporting Disclosure [Text Block]
Public Utilities, Property, Plant and Equipment [Abstract]
PROPERTY, PLANT AND EQUIPMENT
Property, Plant and Equipment Disclosure [Text Block]
Anticipated Business Merger [Axis]
Anticipated Business Merger [Axis]
Anticipated Business Merger [Domain]
Anticipated Business Merger [Domain]
Entergy Corporation
Entergy Corporation [Member]
Entergy Corporation [Member]
Miles of transmission lines
Miles of Transmission Lines
Miles of Transmission Lines
Recapitalization amount
Recapitalization Amount
Recapitalization Amount
Ownership percentage of pro forma shares
Ownership Percentage of Pro Forma Shares
Ownership Percentage of Pro Forma Shares
Gross cash proceeds for assets
Gross Cash Proceeds for Assets
Gross Cash Proceeds for Assets
Schedule of Regulatory Liabilities [Table]
Schedule of Regulatory Liabilities [Table]
Regulatory Liability [Axis]
Regulatory Liability [Axis]
Regulatory Liability [Domain]
Regulatory Liability [Domain]
Accrued Interest on Revenue Deferrals
Accrued Interest on Revenue Deferrals [Member]
Accrued Interest on Revenue Deferrals [Member]
Accrued Asset Removal Costs
Asset Retirement Obligation Costs [Member]
FERC Audit Refund
FERC Audit Refund [Member]
FERC Audit Refund [Member]
Accrued Interest for FERC Refund
Accrued Interest for FERC Refund [Member]
Accrued Interest for FERC Refund [Member]
Regulatory Liabilities
Regulatory Liabilities [Line Items]
Regulatory liabilities - revenue deferrals, including accrued interest
Regulatory Liability, Revenue Deferrals, Current
Carrying amount as of the balance sheet date of deferred revenue for our regulated operating subsidiaries when the actual net revenue requirement for the reporting period is lower than the amounts billed relating to that reporting period. The revenue deferral is expected to be refunded through a reduction in transmission rates within one year.
Current regulatory liability
Regulatory Liability, Current
Regulatory liabilities - revenue deferrals, including accrued interest
Regulatory Liability, Revenue Deferral, Noncurrent
Carrying amount as of the balance sheet date of deferred revenue for our regulated operating subsidiaries when the actual net revenue requirement for the reporting period is lower than the amounts billed relating to that reporting period. The revenue deferral is expected to be refunded through a reduction in transmission rates within two years.
Non-current regulatory liability
Regulatory Liability, Noncurrent
Regulatory liability
Regulatory Liabilities
Changes in Regulatory Assets and Liabilities (Net) Associated with Regulated Operating Subsidiaries' Formula Rate Revenue Accruals and Deferrals, Including Accrued Interest
Schedule Of Changes In Regulatory Assets And Liabilities Formula Rate Revenue Accruals And Deferrals Table Text Block
The changes in regulatory assets and liabilities (net) associated with our Regulated Operating Subsidiaries' formula rate revenue accruals and deferrals, including accrued interest, from the beginning of the period through the current reporting period.
Regulatory Assets and Liabilities Associated with Regulated Operating Subsidiaries' Formula Rate Revenue Accruals and Deferrals
Schedule of Regulatory Assets and Liabilities Associated with Regulated Operating Subsidiaries' Formula Rate Revenue Accruals and Deferrals
Schedule of current and non-current regulatory assets and liabilities associated with our Regulated Operating Subsidiaries' formula rate revenue accruals and deferrals recorded in our condensed consolidated statement of financial position.
Defined Benefit Plan, Asset Categories
Defined Benefit Plan, Asset Categories [Axis]
Plan Asset Categories [Domain]
Plan Asset Categories [Domain]
Fixed Income Funds
Fixed Income Funds [Member]
Asset allocation
Defined Benefit Plan, Actual Plan Asset Allocations
SUPPLEMENTARY QUARTERLY FINANCIAL INFORMATION (UNAUDITED)
Quarterly Financial Information [Text Block]
Stockholders' Equity Note [Abstract]
Schedule of Stock by Class [Table]
Stock Issuance, Name of Arrangement [Axis]
Stock Issuance, Name of Arrangement [Axis]
Stock Issuance, Name of Arrangement [Axis]
Name of Arrangement [Domain]
Name of Arrangement [Domain]
Name of Arrangement [Domain]
Sales Agency Financing Agreement
Sales Agency Financing Agreement [Member]
Sales Agency Financing Agreement [Member]
Class of Stock [Axis]
Class of Stock [Domain]
Preferred Stock
Preferred Stock [Member]
Class of Stock [Line Items]
Common stock, par value
Common Stock, Par or Stated Value Per Share
Common stock - authorized shares
Preferred stock - authorized shares
Preferred Stock, Shares Authorized
Common stock, shares
Preferred stock - outstanding shares
Preferred Stock, Shares Outstanding
Common stock - shareholders of record
Common Stock, Shareholders of Record
Common Stock, Shareholders of Record
Shares issued of preferred stock
Preferred Stock, Shares Issued
Common stock issuable shares value
Common Stock Issuable Shares Value
Common Stock Issuable Shares, Value
Description of restriction
Restriction on Stock Issuance, Description
Restriction on Stock Issuance, Description
Restriction period
Restriction on Stock Issuance, Period
Restriction on Stock Issuance, Period
Commission rate
Commission Rate
Commission Rate
Shares issued
Agreement Name [Axis]
Agreement Name [Axis]
Agreement Name [Axis]
Agreement Name [Domain]
Agreement Name [Domain]
[Domain] for Agreement Name [Axis]
Purchase and Sale Agreement for Ancillary Services
Purchase and Sale Agreement for Ancillary Services [Member]
Purchase and Sale Agreement for Ancillary Services [Member]
Easement Agreement
Easement Agreement [Member]
Easement Agreement [Member]
Maintenance Agreement
Maintenance Agreement [Member]
Maintenance Agreement [Member]
Agreement Counterparty [Axis]
Agreement Counterparty [Axis]
Agreement Counterparty [Axis]
Agreement Counterparty [Domain]
Agreement Counterparty [Domain]
[Domain] for Agreement Counterparty [Axis]
Midwest-Kansas Electric Company LLC
Mid-Kansas Electric Company LLC [Member]
Mid-Kansas Electric Company LLC [Member]
Midwest Energy
Midwest Energy [Member]
Midwest Energy [Member]
Guarantor Obligations, Nature [Axis]
Guarantor Obligations, Nature [Axis]
Guarantor Obligations, Nature [Domain]
Guarantor Obligations, Nature [Domain]
Other Condition
Other Condition [Member]
Other Condition
Original term
Agreement, Original Term
Agreement, Original Term
Automatic renewal term
Agreement, Automatic Renewal Term
Agreement, Automatic Renewal Term
Annual cost
Annual Cost
Annual Cost
Number of automatic renewals
Number of Automatic Renewals
Number of Automatic Renewals
Rate of return on equity
Rate Of Return On Equity
Rate Of Return On Equity
Reduced rate of return on equity
Reduced Rate of Return on Equity
Reduced Rate of Return on Equity
SHARE-BASED COMPENSATION
Disclosure of Compensation Related Costs, Share-based Payments [Text Block]
EARNINGS PER SHARE
Earnings Per Share [Text Block]
Schedule of Regulatory Assets
Schedule of Regulatory Assets [Table Text Block]
Schedule of Regulatory Liabilities
Schedule of Regulatory Liabilities [Table Text Block]
COMMITMENTS AND CONTINGENT LIABILITIES
Commitments and Contingencies Disclosure [Text Block]
Cash and Cash Equivalents
Cash and Cash Equivalents [Member]
Pooled Seperate Accounts - U.S. Equity Funds
Pooled Seperate Accounts - U.S. Equity Funds [Member]
Pooled Seperate Accounts - U.S. Equity Funds [Member]
Pooled Seperate Accounts - International Equity Funds
Pooled Seperate Accounts - International Equity Funds [Member]
Pooled Seperate Accounts - International Equity Funds [Member]
Pooled Seperate Accounts - Fixed Income Securities
Mutual Funds - Equity Securities
Mutual Funds - Equity Securities [Member]
Mutual Funds - Equity Securities [Member]
Mutual Funds - Fixed Income Securities
Mutual Funds - Fixed Income Securities [Member]
Mutual Funds - Fixed Income Securities [Member]
Guaranteed Deposit
Guaranteed Deposit [Member]
Guaranteed Deposit [Member]
Fair Value, Hierarchy [Axis]
Fair Value, Measurements, Fair Value Hierarchy [Domain]
Fair value amount
Schedule of Expected Amortization Expense
Schedule of Expected Amortization Expense [Table Text Block]
Schedule of Future Minimum Lease Payments for Operating Leases
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]
Schedule of Regulatory Assets [Table]
Schedule of Regulatory Assets [Table]
Revenue Accruals, Including Accrued Interest
Revenue Accruals, Including Accrued Interest [Member]
Revenue Accruals, Including Accrued Interest [Member]
Accrued Interest on Revenue Accruals
Accrued Interest on Revenue Accruals [Member]
Accrued Interest on Revenue Accruals [Member]
Income Taxes Recoverable Related to AFUDC Equity
Income Taxes Recoverable Related to AFUDC Equity [Member]
Income Taxes Recoverable Related to AFUDC Equity [Member]
Start-up and Development
Start-up and Development [Member]
Start-up and Development [Member]
KETA and Kansas V-Plan Projects
KETA and Kansas V-Plan Projects [Member]
KETA and Kansas V-Plan Projects [Member]
Pension and Postretirement
Pension Costs [Member]
Implementation of the Michigan Corporate Income Tax
Implementation of the Michigan Corporate Income Tax [Member]
Implementation of the Michigan Corporate Income Tax [Member]
Other
Other Costs [Member]
Other Costs [Member]
Regulatory Assets
Regulatory Assets [Line Items]
Regulatory assets - revenue accruals, including accrued interest
Regulatory Assets, Revenue Accruals, Current
Carrying amount as of the balance sheet date of accrued revenue for our regulated operating subsidiaries when the actual net revenue requirement for the reporting period is higher than the amounts billed relating to that reporting period. The revenue accrual is expected to be recovered through transmission rates within one year.
Current regulatory asset
Regulatory Assets, Current
Regulatory assets - revenue accruals, including accrued interest
Regulatory Assets, Revenue Accrual, Noncurrent
Carrying amount as of the balance sheet date of accrued revenue for our regulated operating subsidiaries when the actual net revenue requirement for the reporting period is higher than the amounts billed relating to that reporting period. The revenue accrual is expected to be recovered through transmission rates within two years.
Non-current regulatory asset
Regulatory Assets, Noncurrent
Accumulated amortization
Regulatory Assets, Accumulated Amortization
Regulatory Assets, Accumulated Amortization
Schedule of Long-term Debt Instruments [Table]
Term Loan Credit Agreement, due December 31, 2013
Term Loan Credit Agreement, due December 31, 2013 [Member]
Term Loan Credit Agreement, due December 31, 2013 [Member]
Borrowing capacity
Short-term Debt, Maximum Borrowing Capacity
Short-term Debt, Maximum Borrowing Capacity
Principle amount
Debt Instrument, Face Amount
Supplementary Cash Flows Information
Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components
Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components
Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation
Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation
Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation
Components of Income Tax Provision
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current income tax expense
Current Income Tax Expense (Benefit)
Deferred income tax expense
Deferred Income Tax Expense (Benefit), Other
Deferred Income Tax Expense (Benefit), Other
Benefits of operating loss carryforward
Deferred Income Tax, Benefits of Operating Loss Carryforward
Deferred Income Tax, Benefits of Operating Loss Carryforward
Change in Michigan tax law
Deferred Other Tax Expense (Benefit)
Total income tax provision
Statement of Cash Flows [Abstract]
Depreciation and amortization expense
Recognition, refund and collection of revenue accruals and deferrals - including accrued interest
Increase (Decrease) in Regulatory Assets and Liabilities
Other — net
Accounts receivable
Increase (Decrease) in Accounts Receivable
Inventory
Increase (Decrease) in Inventories
Prepaid and other current assets
Accounts payable
Accrued taxes
Increase (Decrease) in Accrued Taxes Payable
Tax benefit for excess tax deductions of share-based compensation
Other non-current assets and liabilities, net
Expenditures for property, plant and equipment
Payments to Acquire Property, Plant, and Equipment
Other
Payments for (Proceeds from) Other Investing Activities
Issuance of long-term debt
Proceeds from Issuance of Long-term Debt
Borrowings under revolving credit agreements
Repayments of revolving credit agreements
Dividends on common stock
Refundable deposits from generators for transmission network upgrades
Refundable Deposits from Generators for Transmission Network Upgrades, Financing Activities
Change in refundable deposits from generators for transmission network upgrades.
Repayment of refundable deposits from generators for transmission network upgrades
Repayment of Refundable Deposits from Generators for Transmission Network Upgrades
Repayments of refundable deposits from generators for transmission network upgrades.
Other
Net cash provided by (used in) financing activities
NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS
Future Amortization Expense
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2013
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months
2014
Finite-Lived Intangible Assets, Amortization Expense, Year Two
2015
Finite-Lived Intangible Assets, Amortization Expense, Year Three
2016
Finite-Lived Intangible Assets, Amortization Expense, Year Four
2017
Finite-Lived Intangible Assets, Amortization Expense, Year Five
2018 and thereafter
Finite-Lived Intangible Assets, Amortization Expense, after Year Five
Income Tax Reconciliation
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Income tax expense at 35% statutory rate
Income Tax Reconciliation, Income Tax Expense (Benefit), at Federal Statutory Income Tax Rate
State income taxes (net of federal benefit)
Income Tax Reconciliation, State and Local Income Taxes
AFUDC equity
Income Tax Reconciliation, AFUDC Equity
Income Tax Reconciliation, AFUDC Equity
Other - net
Income Tax Reconciliation, Other Adjustments
Federal statutory income tax rate
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate
Schedule of Retirement Benefits Disclosures [Table]
Schedule of Retirement Benefits Disclosures [Table]
Defined Contribution Plan
Defined Contribution Retirement Savings Plan [Member]
Defined Contribution Retirement Savings Plan [Member]
Retirement Benefits Disclosure
Retirement Benefits Disclosure [Line Items]
Retirement Benefits Disclosure [Line Items]
Expected contribution
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year
Gain in other income associated with realized and unrealized gains and losses
Defined Benefit Plan, Net Realized and Unrealized Gain (Loss) Recognized in Other Income
Defined Benefit Plan, Net Realized and Unrealized Gain (Loss) Recognized in Other Income
Employer match contribution
Defined Contribution Plan, Cost Recognized
GOODWILL AND INTANGIBLE ASSETS
Goodwill and Intangible Assets Disclosure [Text Block]
Document and Entity Information [Abstract]
Document and Entity Information [Abstract]
Entity Registrant Name
Entity Registrant Name
Entity Central Index Key
Entity Central Index Key
Document Type
Document Type
Trading Symbol
Trading Symbol
Document Period End Date
Document Period End Date
Amendment Flag
Amendment Flag
Document Fiscal Year Focus
Document Fiscal Year Focus
Document Fiscal Period Focus
Document Fiscal Period Focus
Current Fiscal Year End Date
Current Fiscal Year End Date
Entity Filer Category
Entity Filer Category
Entity Well-known Seasoned Issuer
Entity Well-known Seasoned Issuer
Entity Voluntary Filers
Entity Voluntary Filers
Entity Current Reporting Status
Entity Current Reporting Status
Entity Common Stock, Shares Outstanding
Entity Common Stock, Shares Outstanding
Entity Public Float
Entity Public Float
Schedule of Share-based Compensation Cost Allocation
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]
Schedule of Stock Options Activity
Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]
Schedule of Stock Options Valuation Assumptions
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
Schedule of Restricted Stock Activity
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]
Schedule of Deferred Stock Units Activity
Schedule of Other Share-based Compensation, Activity [Table Text Block]
Derivative [Table]
Derivative [Table]
Derivative Instrument Risk [Axis]
Derivative Contract Type [Domain]
Interest Rate Swaps
Derivative [Line Items]
Debt
Notional amount
Notional Amount of Interest Rate Derivatives
Fixed interest rate
Derivative, Fixed Interest Rate
Original term
Derivative Instrument, Original Term
Derivative Instrument, Original Term
Ineffectiveness recorded in the consolidated statement of operations
Gain (Loss) on Interest Rate Cash Flow Hedge Ineffectiveness
Fair value of derivative instruments, asset
Fair value of derivative instruments, liability
SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF REGISTRANT
Condensed Financial Information of Parent Company Only Disclosure [Text Block]
2013
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months
2014
Defined Benefit Plan, Expected Future Benefit Payments, Year Two
2015
Defined Benefit Plan, Expected Future Benefit Payments, Year Three
2016
Defined Benefit Plan, Expected Future Benefit Payments, Year Four
2017
Defined Benefit Plan, Expected Future Benefit Payments, Year Five
2018 through 2022
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter
Schedule of Segment Reporting Information, by Segment [Table]
Schedule of Segment Reporting Information, by Segment [Table]
Regulated Operating Subsidiaries
Regulated Operation [Member]
ITC Holdings and Other
Parent Company And Nonregulated Operating Subsidiaries [Member]
Includes all amounts for the Parent Company and any non-regulated operating subsidiaries included with the consolidated statements of operations.
Reconciliations and Eliminations
Reconciliations and Eliminations [Member]
Reconciliations and Eliminations [Member]
Segment Reporting Information
Segment Reporting Information [Line Items]
Income before income taxes
Property, plant and equipment, net
Property, Plant and Equipment, Net
Total assets
Capital expenditures
Maturities of Debt
Maturities of Debt [Abstract]
Maturities of Debt [Abstract]
Schedule of Earnings Per Share, Basic and Diluted, by Common Class [Table]
Schedule of Earnings Per Share, Basic and Diluted, by Common Class [Table]
Schedule of Earnings Per Share, Basic and Diluted, by Common Class [Table]
Common Shares
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Numerator:
Income Amounts Attributable to Parent, Disclosures [Abstract]
Dividends declared
Distributed Earnings
Undistributed earnings
Undistributed Earnings, Basic
Percentage allocated to common shares
Percentage allocated to common shares
Percentage of earnings allocated to common shares
Numerator for basic and diluted earnings per common share
Income Loss From Continuing Operations Available To Common Shareholders
Income (Loss) from Continuing Operations Available to Common Shareholders
Denominator:
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Denominator for basic earnings per common share - weighted-average common shares
Weighted Average Number of Shares Outstanding, Basic
Incremental shares for stock options and employee stock purchase plan
Weighted Average Number Diluted Shares Outstanding Adjustment
Denominator for diluted earnings per common share - adjusted weighted-average shares and assumed conversion
Weighted Average Number of Shares Outstanding, Diluted
Per common share net income:
Earnings Per Share [Abstract]
Percentage allocated to common shares:
Percentage Allocated to Common Shares [Abstract]
Percentage Allocated to Common Shares [Abstract]
Weighted-average shares outstanding, participating securities
Weighted-Average Shares Outstanding, Participating Securities
Weighted-average of participating securities used to determine the percentage of earnings allocated to common stock.
Denominator for percentage allocated to common shares - total weighted average shares outstanding
Denominator for Percentage Allocated to Common Shares - Total Weighted-Average Shares Outstanding
Total weighted-average of common shares and participating securities used as the denominator to determine the percentage of earnings allocated to common shares.
JOINTLY OWNED UTILITY PLANT/COORDINATED SERVICES
Jointly Owned Utility Plant Coordinated Services [Text Block]
Jointly Owned Utility Plant/Coordinated Services [Text Block]
Plan Name [Axis]
Plan Name [Axis]
Plan Name [Domain]
Plan Name [Domain]
Long Term Incentive Plan
Long Term Incentive Plan [Member]
Long Term Incentive Plan [Member]
Restricted Stock
Restricted Stock [Member]
Employee Stock Purchase Plan
Employee Stock Purchase Plan [Member]
Employee Stock Purchase Plan [Member]
State Tax Jurisdiction
State and Local Jurisdiction [Member]
Authorized shares
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized
Authorized shares of common stock other than options
Share Based Compensation Arrangement By Share Based Payment Award, Number of Shares Authorized of Common Stock Other Than Options or Stock Appreciation Rights
Share Based Compensation Arrangement By Share Based Payment Award, Number of Shares Authorized of Common Stock Other Than Options or Stock Appreciation Rights
Shares available for future issuance
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant
Outstanding options
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options
Exercisable options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number
Tax effects of the excess tax deductions
Vesting period
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period
Term from grant date
Share-based Compensation Arrangement by Share-based Payment Award, Term From Grant Date
Share-based Compensation Arrangement by Share-based Payment Award, Term From Grant Date
Outstanding options - Aggregate intrinsic value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value
Outstanding options - Weighted average remaining contractual term
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term
Exercisable options - Aggregate intrinsic value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value
Exercisable options - Weighted average remaining contractual term
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term
Exercised options - Aggregate intrinsic value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value
Unrecognized compensation cost related to unvested awards - Total amount
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized
Unrecognized compensation cost related to unvested awards - Period for recognition
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition
Options expected to vest - Outstanding
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number
Options expected to vest - Weighted average exercise price
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price
Options expected to vest - Aggregate intrinsic value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value
Options expected to vest - Weighted average remaining contractual term
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term
Weighted average remaining contractual term
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms
Outstanding shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number
Granted - Weighted average grant date fair value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value
Aggregate fair value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Fair Value
Vested in period - Total fair value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value
Awards expected to vest - Outstanding
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Shares Expected to Vest, Outstanding, Number
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Shares Expected to Vest, Outstanding, Number
Awards expected to vest - Weighted average fair value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Shares Expected to Vest, Weighted Average Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Shares Expected to Vest, Weighted Average Fair Value
Awards expected to vest - Aggregate intrinsic value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Shares Expected to Vest, Aggregate Intrinsic Value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Shares Expected to Vest, Aggregate Intrinsic Value
Awards expected to vest - Weighted average remaining contractual term
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Shares Expected to Vest, Weighted Average Remaining Contractual Term
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Shares Expected to Vest, Weighted Average Remaining Contractual Term
Stock purchased
Proceeds from the sale of common stock
Allocated share-based compensation expense
Allocated Share-based Compensation Expense
Schedule of Public Utility Property, Plant, and Equipment
Schedule of Public Utility Property, Plant, and Equipment [Table Text Block]
Options Roll Forward
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Exercisable options - Weighted average exercise price
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price
Beginning balance
Beginning - Weighted average exercise price
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price
Granted
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross
Granted - Weighted average exercise price
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price
Excercised
Excercised - Weighted average exercise price
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price
Forfeited
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period
Forfeited - Weighted average exercise price
Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price
Ending balance
Ending - Weighted average exercise price
Restricted Stock and Deferred Stock Rollforwards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Beginning balance
Beginning - Weighted average grant date fair value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value
Granted
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period
Vested
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period
Vested - Weighted average grant date fair value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value
Forfeited
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period
Forfeited - Weighted average grant date fair value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value
Ending balance
Ending - Weighted average grant date fair value
Michigan
Michigan [Member]
Michigan
Amortization expense
Amortization of Acquisition Costs
Equity component of carrying charges
Equity Component of Carrying Charges
Equity Component of Carrying Charges
In-service gross property, plant and equipment
In-service Gross Property, Plant and Equipment
In-service Gross Property, Plant and Equipment
State income tax rate
State Income Tax Rate
State Income Tax Rate
Beginning balance
Net Regulatory (Liabilities) Assets
Net Regulatory (Liabilities) Assets
Net refund of 2010 revenue deferrals and accruals, including interest
Net Refunds Collections Of Revenue Deferrals And Accruals Including Interest
Net Refunds (Collections) Of Revenue Deferrals and Accruals, Including Interest, During the Period
Net revenue deferrals for the year ended December 31, 2012
Net Revenue Accruals Deferrals For The Period
Net Revenue Accruals Deferrals For The Period
Net accrued interest payable for the year ended December 31, 2012
Net Accrued Interest Receivable Payable For The Period
Net Accrued Interest Receivable Payable For The Period
Ending balance
DEBT
Debt Disclosure [Text Block]
Public Utility, Property, Plant and Equipment [Table]
Regulation Status [Axis]
Regulated and Unregulated Operation [Domain]
ITC Holdings and Other
Unregulated Operation [Member]
Public Utility, Property, Plant and Equipment
Public Utility, Property, Plant and Equipment [Line Items]
Property, plant and equipment in service
Public Utilities, Property, Plant and Equipment, In Service
Public Utilities, Property, Plant and Equipment, In Service
Construction work in progress
Public Utilities, Property, Plant and Equipment, Construction Work in Progress
Capital equipment inventory
Public Utilities, Property, Plant and Equipment, Equipment
Other
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment
ITC Holdings and other
Property, Plant and Equipment, Gross
Total
Public Utilities, Property, Plant and Equipment, Plant in Service
Less: Accumulated depreciation and amortization
Property, plant and equipment - net
Public Utilities, Property, Plant and Equipment, Net
Income Tax [Table]
Income Taxes [Table]
Income Taxes [Table]
Income Tax
Income Taxes [Line Items]
Income Taxes [Line Items]
Federal income tax NOLs
Operating Loss Carryforwards
State income tax NOLs
STOCKHOLDERS EQUITY
Stockholders' Equity Note Disclosure [Text Block]
Regulatory Asset and Liability [Axis]
Regulatory Asset and Liability [Axis]
Regulatory Asset and Liability [Axis]
Regulatory Asset and Liability [Domain]
Regulatory Asset and Liability [Domain]
Regulatory Asset and Liability [Domain]
Current assets
Current liabilities
Net balance
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table]
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table]
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs, by Report Line [Axis]
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs, by Report Line [Axis]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Report Line [Domain]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Report Line [Domain]
Operation and Maintenance Expenses
Operation and Maintenance Expenses [Member]
Operation and Maintenance Expenses [Member]
General and Administrative Expenses
General and Administrative Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Amounts capitalized to property, plant and equipment
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount
Total share-based compensation
Total tax benefit recognized in the consolidated statement of operations
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense
Total net investment including assets under construction
Jointly Owned Utility Plant, Net Ownership Amount
Ownership percentage
Jointly Owned Utility Plant, Proportionate Ownership Share
Number of transmission lines
Number of Transmission Lines
Number of Transmission Lines
TOTAL OTHER COMPREHENSIVE (LOSS) INCOME, NET OF TAX
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent
REGULATORY ASSETS AND LIABILITIES
Schedule of Regulatory Assets and Liabilities [Text Block]
INCOME TAXES
Income Tax Disclosure [Text Block]
Service cost
Interest cost
Expected return on plan assets
Defined Benefit Plan, Expected Return on Plan Assets
Amortization of prior service cost
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)
Amortization of unrecognized loss
Defined Benefit Plan, Amortization Of Unrecognized Gains Losses
The amount of (gains) or losses unrecognized in net periodic benefit cost.
Net cost
Defined Benefit Plan, Net Periodic Benefit Cost
Schedule of Jointly Owned Utility Plant
Schedule of Jointly Owned Utility Plants [Table Text Block]
Interest paid (net of interest capitalized)
Additions to property, plant and equipment
Capital Expenditures Incurred but Not yet Paid
Allowance for equity funds used during construction
Accounts receivable
Accounts Receivable, Net, Current
Inventory
Inventory, Net
Deferred income taxes
Deferred Tax Assets, Net of Valuation Allowance, Current
Other
Property, plant and equipment (net of accumulated depreciation and amortization of $1,269,810 and $1,193,164, respectively)
Intangible assets (net of accumulated amortization of $18,397 and $15,276, respectively)
Other regulatory assets
Deferred financing fees (net of accumulated amortization of $17,838 and $14,594, respectively)
Other
Accrued taxes
Taxes Payable, Current
Refundable deposits from generators for transmission network upgrades
Refundable Deposits From Generators For Transmission Network Upgrades, Current
For utilities only, represents the current portion (expected to be paid within 1 year) of the carrying amount of the liability as of the balance sheet date for payments received by a utility from its customers in advance of performing its obligations under terms of its construction agreements.
Other
Deferred income taxes
Deferred Tax Liabilities, Net, Noncurrent
Regulatory liabilities - accrued asset removal costs
Refundable deposits from generators for transmission network upgrades
Refundable Deposits From Generators For Transmission Network Upgrades, Noncurrent
For utilities only, represents the noncurrent portion of the carrying amount of the liability as of the balance sheet date for payments received by a utility from its customers in advance of performing its obligations under terms of its construction agreements.
Other
Long-term debt
Commitments and contingent liabilities (Notes 4 and 16)
Commitments and Contingencies