Amounts Recorded in Consolidated Balance Sheet and Accumulated Other Comprehensive Income (Detail) (CAD) In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Current liabilities	(53)		(52)
Other long-term obligations	(1,448)	[1]	(2,717)	[1]
Pension benefits
Defined Benefit Plan Disclosure [Line Items]
Current liabilities	(25)		(24)
Other long-term obligations	(973)		(2,198)
Total recorded	(998)		(2,222)
Net actuarial loss/(gain)	2,303		3,210
Prior service cost	62		85
Total recorded in accumulated other comprehensive income, before tax	2,365		3,295
Other post-retirement benefits
Defined Benefit Plan Disclosure [Line Items]
Current liabilities	(28)		(28)
Other long-term obligations	(475)		(519)
Total recorded	(503)		(547)
Net actuarial loss/(gain)	64		124
Total recorded in accumulated other comprehensive income, before tax	64		124

[1] Total recorded employee retirement benefit obligations also include $53 million in current liabilities (2012 - $52 million).