Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2017

Commitments and Contingencies Disclosure [Abstract]

Minimum Future Lease Payments Under Operating Leases

As at December 31, 2017, the Company’s commitments under operating leases were estimated at $351 million in aggregate, with minimum annual payments in each of the next five years and thereafter as follows: 

(in millions of Canadian dollars)	Operating leases
2018	$	71
2019	57
2020	45
2021	38
2022	31
Thereafter	109
Total minimum lease payments	$	351