Finance Lease Receivables (Details) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Disclosure of recognised finance lease as assets by lessee [line items]
Minimum lease payments	CAD 318	CAD 1,137
Present value of minimum lease payments	274	721
Less: unearned finance lease income	44	592
Less: unearned finance lease income, present value	0	0
Add: unguaranteed residual value	0	233
Add: unguaranteed residual value, present value	0	57
Total finance lease receivables	274	778
Current portion of finance lease receivables (Note 12)	59	59
Long-term portion of finance lease receivables (Note 7)	215	719
Within one year
Disclosure of recognised finance lease as assets by lessee [line items]
Minimum lease payments	68	124
Present value of minimum lease payments	66	119
Second to fifth years inclusive
Disclosure of recognised finance lease as assets by lessee [line items]
Minimum lease payments	110	376
Present value of minimum lease payments	82	291
More than five years
Disclosure of recognised finance lease as assets by lessee [line items]
Minimum lease payments	140	637
Present value of minimum lease payments	CAD 126	CAD 311

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 the discounted unguaranteed residual value of assets subject to finance leases. Unguaranteed residual value is the portion of the residual value of the underlying asset, the realisation of which by a lessor is not assured or is guaranteed solely by a party related to the lessor. Finance lease is a lease that transfers substantially all the risks and rewards incidental to ownership of an underlying asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2019-01-01
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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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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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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]

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Discounted unguaranteed residual value of assets subject to finance lease, present value

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Unearned finance income relating to finance lease payments receivable, present value

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No definition available.

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