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Share-Based Compensation - Summary of Number of Awards Granted and Grand Date Fair Value (Detail) - $ / shares shares in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Deferred Tax Assets Valuation Allowance [Line Items] |  |  |
Grant date fair value (in usd per share) | $ 9.44 |  |
TSR Awards |  |  |
Deferred Tax Assets Valuation Allowance [Line Items] |  |  |
Number of shares (in shares) | 139 | 136 | 55
Grant date fair value (in usd per share) | $ 10.88 | $ 9.28 | $ 24.65
ROIC Awards |  |  |
Deferred Tax Assets Valuation Allowance [Line Items] |  |  |
Number of shares (in shares) | 157 | 174 | 55
Grant date fair value (in usd per share) | $ 9.44 | $ 7.93 | $ 24.55

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- Definition Number of equity instruments other than options outstanding, including both vested and non-vested instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i) -URI http://asc.fasb.org/extlink&oid=120381028&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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