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Share Based Payments - Summary of Stock Option Activity (Parenthetical) (Detail) | 3 Months Ended
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Mar. 31, 2018 shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] |
Stock options exercised on cashless basis | 80,000
Number of common stock shares withheld | 17,091

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- Definition Stock issued during period shares stock options exercised on cashless basis. + References No definition available. + Details
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Balance Type: | na
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- References No definition available. + Details
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Balance Type: | na
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