Loss Per Share - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Contingent Consideration Cash Payments | $ 0.1 | $ 0.8 | $ 0.5 |
| Potentially dilutive shares included in the computation of basic and diluted earnings per share | 53,335 | 292,967 | |
| Contingent payment of stock issued for acquisitions of businesses | $ 0.6 | $ 6.5 | |
| Stock Options | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Antidilutive number of options outstanding | 24,875 | 27,828 | 31,483 |
| Average exercise price | $ 44.45 | $ 44.76 | $ 43.64 |
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- Definition Business Combination Contingent Consideration Cash Payments No definition available.
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- Definition Contingent consideration for acquisitions payable in common stock or cash, at company's option, if certain performance criteria are met. No definition available.
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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of contingently issuable shares. Contingently issuable shares are those shares that are issuable for little or no cash contingent on certain conditions being met. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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