Estimated 2014 Amortization from Accumulated Other Comprehensive Income (Detail) (CAD) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Pension benefits
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss/(gain)	169	[1]
Prior service cost	23	[2]
Other post-retirement benefits
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss/(gain)	5	[1]

[1] The company amortizes the net balance of actuarial loss/(gain) as a component of net periodic benefit cost over the average remaining service period of active plan participants.

[2] The company amortizes prior service cost on a straight-line basis.