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Basis of Presentation and New Accounting Pronouncements - Additional Information (Detail)	Sep. 30, 2019	Dec. 31, 2018
Unnamed Corporate Joint Venture [Member]
Basis Of Presentation [Line Items]
Equity method ownership percentage in joint venture	37.50%	49.00%

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- References

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 equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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