Variable Interest Entities (Details) CAD in Millions	12 Months Ended
	Dec. 31, 2015 CAD
Variable Interest Entity [Line Items]
Lease payments after tax	CAD 107
Future minimum lease payments before tax	553
Variable Interest Entity [Member]
Variable Interest Entity [Line Items]
Lease payments after tax	11
Future minimum lease payments before tax	CAD 233
Period over which lease payments will be paid	15 years