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Capital Stock - Additional Information (Detail) |  | 12 Months Ended
--- | --- | ---
Nov. 13, 2017 shares | Dec. 31, 2017 Vote shares
Equity [Abstract] |  |
Preference shares included in authorized capital stock |  | 99,760,000
Shares issued or outstanding |  | 0
Number of votes per share | Vote |  | 1
Number of common stock shares to be purchased under the Bid | 35,800,000 |
Percentage of issued and outstanding common shares | 10.00% |
Commencement date of Bid |  | Nov. 15, 2017
Termination date of Bid |  | Nov. 14, 2018

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- Definition Number of common stock shares to be repurchased. + References No definition available. + Details
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- Definition The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. + 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(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt. + 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(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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