Number of joint ventures in which the Company has an interest.

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

For an unclassified balance sheet, amounts due from an entity in which the reporting entity shares joint control with another party or group.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
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-Publisher FASB
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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

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- Definition

The cash outflow from advancing money to an affiliate (an entity that is related but not strictly controlled by the entity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Related Party Transactions (Contractual Joint Ventures) (Narrative) (Details) CAD in Millions	3 Months Ended
	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2017 CAD	Mar. 31, 2017 USD ($)	Dec. 31, 2016 CAD	Dec. 31, 2016 USD ($)
Performance Guarantees [Member]
Related Party Transaction [Line Items]
Guarantees issued, related parties				$ 15,200,000		$ 72,900,000
Joint Venture [Member] \| Joint Venture A That Provides Electrical Transmission Infrastructure Services [Member]
Related Party Transaction [Line Items]
Proportionately consolidated non-controlled joint venture, ownership percentage			85.00%	85.00%
Joint Venture [Member] \| Joint Venture B That Provides Electrical Transmission Infrastructure Services [Member]
Related Party Transaction [Line Items]
Proportionately consolidated non-controlled joint venture, ownership percentage			85.00%	85.00%
Joint Venture [Member] \| Joint Venture C That Provides Electrical Transmission Infrastructure Services [Member]
Related Party Transaction [Line Items]
Proportionately consolidated non-controlled joint venture, ownership percentage			90.00%	90.00%
Joint Venture [Member] \| Joint Ventures That Provide Electrical Transmission Infrastructure Services [Member]
Related Party Transaction [Line Items]
Number of joint ventures			3	3
Joint Venture [Member] \| Pacer [Member]
Related Party Transaction [Line Items]
Proportionately consolidated non-controlled joint venture, ownership percentage			35.00%	35.00%
Joint Venture [Member] \| Pacer [Member] \| Performance Guarantees [Member]
Related Party Transaction [Line Items]
Guarantees issued, related parties \| CAD			CAD 132.1		CAD 132.1
Joint Venture [Member] \| Pacer [Member] \| Canadian Dollars [Member]
Related Party Transaction [Line Items]
Revenue, related party	$ 100,000	$ 300,000
Joint Venture [Member] \| Pacer [Member] \| Canadian Dollars [Member] \| Financing Support [Member]
Related Party Transaction [Line Items]
Project-related financing provided, related party	$ 800,000
Additional amounts committed, related party				$ 0
Joint Venture [Member] \| Pacer [Member] \| Canadian Dollars [Member] \| Performance Guarantees [Member]
Related Party Transaction [Line Items]
Guarantees issued, related parties				99,200,000		98,300,000
Joint Venture [Member] \| Pacer [Member] \| Canadian Dollars [Member] \| Accounts Receivable [Member]
Related Party Transaction [Line Items]
Receivables, related party, unincorporated joint venture				$ 600,000		$ 700,000