Finance Lease Receivables (Details) - CAD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Disclosure of recognised finance lease as assets by lessee [line items]
Minimum lease payments	$ 250	$ 318
Present value of minimum lease payments	215	274
Less: unearned finance lease income	35	44
Less: unearned finance lease income, present value	0	0
Total finance lease receivables	215	274
(Note 13)	24	59
Long-term portion of finance lease receivable (Note 8)	191	215
Within one year
Disclosure of recognised finance lease as assets by lessee [line items]
Minimum lease payments	30	68
Present value of minimum lease payments	29	66
Second to fifth years inclusive
Disclosure of recognised finance lease as assets by lessee [line items]
Minimum lease payments	80	110
Present value of minimum lease payments	74	82
More than five years
Disclosure of recognised finance lease as assets by lessee [line items]
Minimum lease payments	140	140
Present value of minimum lease payments	$ 112	$ 126

The amount of current finance lease receivables. [Refer: Finance lease receivables]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The amount of future minimum sublease payments expected to be received under non-cancellable subleases for finance leases. Minimum lease payments are payments over the lease term that the lessee is, or can be, required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with: (a) for a lessee, any amounts guaranteed by the lessee or by a party related to the lessee; or (b) for a lessor, any residual value guaranteed to the lessor by: (i) the lessee; (ii) a party related to the lessee; or (iii) a third party unrelated to the lessor that is financially capable of discharging the obligations under the guarantee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of receivables related to finance leases.

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The present value of minimum finance lease payments receivable. Minimum lease payments are payments over the lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with: (a) for a lessee, any amounts guaranteed by the lessee or by a party related to the lessee; or (b) for a lessor, any residual value guaranteed to the lessor by: (i) the lessee; (ii) a party related to the lessee; or (iii) a third party unrelated to the lessor that is financially capable of discharging the obligations under the guarantee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of non-current finance lease receivables. [Refer: Finance lease receivables]

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- Definition

The amount of unearned finance income relating to the finance lease payments receivable. Finance lease is a lease that transfers substantially all the risks and rewards incidental to ownership of an underlying asset. [Refer: Finance income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Unearned finance income relating to finance lease payments receivable, present value

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