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Basis of Presentation and New Accounting Pronouncements - Additional Information (Detail) | Mar. 31, 2019 | Dec. 31, 2018
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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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- 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 + Details
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