General (Details) - CAD ($) $ / shares in Units, $ in Millions		12 Months Ended
	May 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Proceeds received from IPO, net		$ 0.0	$ 1,671.0	$ 0.0
Voting Shares
Gross Proceeds from Issuance Initial Public Offering	$ 1,750.0
Kinder Morgan Canada Limited Partnership [Member]
Noncontrolling Interest, Ownership Percentage by Parent	30.00%
Kinder Morgan, Inc. [Member] | Kinder Morgan Canada Limited Partnership [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	70.00%
KMI Interests
Voting Interest In Entity Held	70.00%
KMI Interests | Voting Shares
Stock Issued During Period, Shares, New Issues			80,700,000
KMI Interests | Kinder Morgan, Inc. [Member]
Controlling Interest, Ownership Percentage by Parent	100.00%
Restricted Voting Shares
Voting Interest In Entity Held	30.00%
Restricted Voting Shares | Voting Shares
Stock Issued During Period, Shares, New Issues	102,942,000		34,300,000
Shares Issued, Price Per Share	$ 17.00