Restricted Stock and Long-term Incentive Retention Award Plan [Abstract]

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Stock Compensation Plan for Non-Employee Directors [Abstract]

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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options.

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Share-based Compensation and Employee Benefits Share-based Compensation (Details) - Restricted Stock [Member] - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016
Kinder Morgan, Inc. Amended and Restated Stock Compensation Plan for Nonemployee Directors[Member] \| Class P
Stock Compensation Plan for Non-Employee Directors [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				250,000
Restricted Stock Incentive Plan Rollforward [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				250,000
Kinder Morgan, Inc. Amended and Restated Stock Compensation Plan for Nonemployee Directors[Member] \| Class P \| Six Month Vesting Period [Member]
Stock Compensation Plan for Non-Employee Directors [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	17,740	31,880	9,580
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures	$ 400,000	$ 400,000	$ 401,000
Restricted Stock Incentive Plan Rollforward [Abstract]
Granted (shares)	17,740	31,880	9,580
Kinder Morgan Inc 2015 Amended and Restated Stock Incentive Plan [Member] \| Class P
Stock Compensation Plan for Non-Employee Directors [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				33,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	3,221,691	2,816,599	1,488,467
Restricted Stock Incentive Plan Rollforward [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				33,000,000
Outstanding at beginning of period (shares)	9,038,137	7,645,105	7,373,294
Outstanding at beginning of period (value per share)	$ 32.72	$ 37.91	$ 37.63
Granted (shares)	3,221,691	2,816,599	1,488,467
Granted (value per share)	$ 19.52	$ 21.36	$ 38.20
Vested (shares)	(1,501,939)	(1,226,652)	(817,797)
Vested (value per share)	$ 36.67	$ 38.53	$ 35.66
Forfeited (shares)	(239,545)	(196,915)	(398,859)
Forfeited (value per share)	$ 28.34	$ 35.74	$ 38.51
Outstanding at end of period (shares)	10,518,344	9,038,137	7,645,105
Outstanding at end of period (value per share)	$ 28.21	$ 32.72	$ 37.91
Intrinsic value of restricted stock vested during the period	$ 30,000,000	$ 25,000,000	$ 31,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Restricted stock future vesting schedule (shares)	9,038,137	7,645,105	7,373,294	10,518,344	9,038,137
Restricted Stock or Unit Expense	$ 65,000,000	$ 66,000,000	$ 52,000,000
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	9,000,000	9,000,000	15,000,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options				$ 112,000,000	$ 133,000,000
KML Equity Based Compensation Plans [Abstract]
Restricted Stock or Unit Expense	65,000,000	66,000,000	52,000,000
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	$ 9,000,000	$ 9,000,000	$ 15,000,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options				$ 112,000,000	$ 133,000,000
Kinder Morgan Inc 2015 Amended and Restated Stock Incentive Plan [Member] \| Class P \| Year 2018 [Member]
Restricted Stock Incentive Plan Rollforward [Abstract]
Outstanding at end of period (shares)	2,272,019
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Restricted stock future vesting schedule (shares)	2,272,019			2,272,019
Kinder Morgan Inc 2015 Amended and Restated Stock Incentive Plan [Member] \| Class P \| Year 2019 [Member]
Restricted Stock Incentive Plan Rollforward [Abstract]
Outstanding at end of period (shares)	4,268,118
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Restricted stock future vesting schedule (shares)	4,268,118			4,268,118
Kinder Morgan Inc 2015 Amended and Restated Stock Incentive Plan [Member] \| Class P \| Year 2020 [Member]
Restricted Stock Incentive Plan Rollforward [Abstract]
Outstanding at end of period (shares)	3,647,967
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Restricted stock future vesting schedule (shares)	3,647,967			3,647,967
Kinder Morgan Inc 2015 Amended and Restated Stock Incentive Plan [Member] \| Class P \| Year 2021 [Member]
Restricted Stock Incentive Plan Rollforward [Abstract]
Outstanding at end of period (shares)	199,850
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Restricted stock future vesting schedule (shares)	199,850			199,850
Kinder Morgan Inc 2015 Amended and Restated Stock Incentive Plan [Member] \| Class P \| Year 2022 [Member]
Restricted Stock Incentive Plan Rollforward [Abstract]
Outstanding at end of period (shares)	65,928
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Restricted stock future vesting schedule (shares)	65,928			65,928
Kinder Morgan Inc 2015 Amended and Restated Stock Incentive Plan [Member] \| Class P \| Thereafter [Member]
Restricted Stock Incentive Plan Rollforward [Abstract]
Outstanding at end of period (shares)	64,462
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Restricted stock future vesting schedule (shares)	64,462			64,462
Kinder Morgan Inc 2015 Amended and Restated Stock Incentive Plan [Member] \| Class P \| Minimum [Member]
Restricted Stock Incentive Plan Rollforward [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Kinder Morgan Inc 2015 Amended and Restated Stock Incentive Plan [Member] \| Class P \| Maximum [Member]
Restricted Stock Incentive Plan Rollforward [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	10 years
KML Restricted Share Unit Plan for Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Restricted Stock or Unit Expense	$ 1,000,000
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	1,000,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options				$ 8,000,000
KML Equity Based Compensation Plans [Abstract]
Restricted Stock or Unit Expense	1,000,000
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	$ 1,000,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options				$ 8,000,000