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Capital Stock - Maximum Number of Shares Outstanding Exercised or Converted (Detail) - Convertible Common Stock [Member] - Subsequent Event [Member]	Mar. 06, 2018 shares
Class of Stock [Line Items]
Common Shares	358,395,997
Stock options	7,661,769
Total number of shares outstanding	366,057,766

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- Definition

Common shares and potentially dilutive securities outstanding.

+ References

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- Definition

Potentially dilutive securities outstanding.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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