The percentage interest in a proportionately consolidated joint venture.

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Amount for accounts payable to related parties.

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For an unclassified balance sheet, amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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

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

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Fair value portion of investments accounted under the equity method.

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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.

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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.

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

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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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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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Related Party Transactions (Contractual Joint Ventures and Investments) (Narrative) (Details) CAD in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 CAD	Sep. 30, 2017 USD ($)	Dec. 31, 2016 CAD	Dec. 31, 2016 USD ($)
Performance Guarantees [Member]
Related Party Transaction [Line Items]
Guarantees issued, related party						$ 119,200,000		$ 72,900,000
Joint Venture [Member] \| Pacer [Member]
Related Party Transaction [Line Items]
Proportionately consolidated non-controlled joint venture, percentage interest					35.00%	35.00%
Joint Venture [Member] \| Pacer [Member] \| Performance Guarantees [Member]
Related Party Transaction [Line Items]
Guarantees issued, related party \| CAD					CAD 132.1		CAD 132.1
Joint Venture [Member] \| Pacer [Member] \| Canadian Dollars [Member]
Related Party Transaction [Line Items]
Revenue, related party	$ 600,000	$ 200,000	$ 900,000	$ 800,000
Joint Venture [Member] \| Pacer [Member] \| Canadian Dollars [Member] \| Financing Support [Member]
Related Party Transaction [Line Items]
Financing or amounts advanced, related party	2,700,000	$ 800,000	5,900,000	$ 5,600,000
Amounts committed, related party						$ 0
Joint Venture [Member] \| Pacer [Member] \| Canadian Dollars [Member] \| Performance Guarantees [Member]
Related Party Transaction [Line Items]
Guarantees issued, related party						105,900,000		98,300,000
Joint Venture [Member] \| Pacer [Member] \| Canadian Dollars [Member] \| Accounts Receivable [Member]
Related Party Transaction [Line Items]
Receivables, related party						$ 900,000		$ 700,000
Equity Investees [Member] \| April 2017 Acquisition [Member]
Related Party Transaction [Line Items]
Financing or amounts advanced, related party			300,000
Equity investment, ownership percentage					40.00%	40.00%
Equity investment, value						$ 400,000
Receivable, related party						300,000
Equity Investees [Member] \| April 2017 Acquisition [Member] \| Subcontracting Arrangements [Member]
Related Party Transaction [Line Items]
Payments, related party			200,000
Payables, related party						0
Management [Member] \| April 2017 Acquisition [Member] \| Financing Arrangements [Member]
Related Party Transaction [Line Items]
Payments, related party	$ 1,400,000		$ 5,300,000
Payables, related party						$ 0