The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
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Amount of interest income earned from interest-bearing assets owed to the entity by related party.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(e))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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EQUITY INVESTMENTS - Loan Receivable From Affiliate (Details) CAD in Millions	12 Months Ended
	Dec. 31, 2017 CAD	Dec. 06, 2017 MXN	Apr. 21, 2017 MXN
Sur de Texas
Equity Investments
Ownership interest (percent)	60.00%
Joint Venture \| Sur de Texas
Equity Investments
Ownership interest (percent)	60.00%
Loans receivable from affiliates	CAD 919
Interest income, related party	CAD 34
Unsecured Loan Facility \| Revolving credit facility \| Joint Venture
Equity Investments
Credit facility, amount \| MXN		MXN 21,300,000,000.0	MXN 13,600,000,000.0