Fair Value Measurements and Derivative Instruments Reporting (Narrative) (Details) $ in Millions	Sep. 30, 2018 CAD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Fair Value Measurements And Derivative Instruments Reporting [Abstract]
Measured at fair value on a non-recurring basis		$ 0
Fair value of land lease	$ 28.6	21,900,000
Cash equivalents		$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- References

No definition available.

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- Definition

Net long-term land leases which are capitalized as part of real property.

+ References

No definition available.

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