Financial Instruments Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Schedule of Fair Value and Carrying Value of Long-term Debt

The carrying values of financial instruments equal or approximate their fair values with the exception of long-term debt:

(in millions of Canadian dollars)	December 31, 2017		December 31, 2016
Long-term debt (including current maturities):
Fair value	$	9,680	$	9,981
Carrying value	8,159		8,684