Income Taxes

3 Months Ended

Mar. 31, 2018

Income Tax Disclosure [Abstract]

Income Taxes

	For the three months ended March 31
(in millions of Canadian dollars)	2018		2017
Current income tax expense	$	81	$	81
Deferred income tax expense	41		67
Income tax expense	$	122	$	148

The effective tax rate in the first quarter was 25.92%, compared to 25.60% for the same period in 2017.

For the three months ended March 31, 2018, the effective tax rate excluding the discrete item of the foreign exchange loss of $49 million on the Company's U.S. dollar-denominated debt was 24.75%.

For the three months ended March 31, 2017, the effective tax rate excluding the discrete items of the management transition recovery of $51 million related to the retirement of the Company's Chief Executive Officer and the foreign exchange gain of $28 million on the Company's U.S. dollar-denominated debt, was 26.50%.