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Shared-Based Compensation - Summary of Number of Awards Granted and Grand Date Fair Value (Detail) shares in Thousands | 9 Months Ended
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Sep. 30, 2018 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Grant Date Fair Value | $ 24.41
TSR Awards |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Number of awards granted in fair values, Shares | shares | 55
Grant Date Fair Value | $ 24.65
ROIC Awards |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Number of awards granted in fair values, Shares | shares | 55
Grant Date Fair Value | $ 24.55

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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. + References No definition available. + Details
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- Definition Net number of non-option equity instruments granted to participants. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. + References No definition available. + Details
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