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Summary of Significant Accounting Policies (Principles of Consolidation) - Additional Information (Detail)	Mar. 31, 2017
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Summary Of Significant Accounting Policies [Line Items]
Equity method investment ownership	20.00%
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Equity method investment ownership	50.00%

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- Definition

Summary Of Significant Accounting Policies [Line Items]

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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