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Common Stock - Additional Information (Detail) - shares shares in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Statement of Stockholders' Equity [Abstract] |  |  |
Common shares outstanding (in Shares) | 3,691 | 3,693 |
Reissued shares during the period, shares (in Shares) | 165 | 83 | 131

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- Definition Number of treasury shares reissued during the period to satisfy equity-based compensation obligations exercised by the holders of such rights. + References No definition available. + Details
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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=6928386&loc=d3e21463-112644 + Details
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Period Type: | instant

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