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Common Stock Repurchase Programs - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019 | Aug. 31, 2018
Common Stock [Line Items] |  |  |
Common stock authorized for repurchase |  |  | $ 500.0
Company's Common stock repurchased |  | $ 107.2 |
Restricted Stock [Member] |  |  |
Common Stock [Line Items] |  |  |
Number of shares withheld to satisfy minimum statutory tax withholding obligations | 0.5 |  |
Amount withheld to satisfy minimum statutory tax withholding obligations | $ 8.5 |  |

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- Definition Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585 + Details
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- Definition Amount remaining of a stock repurchase plan authorized. + References No definition available. + Details
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- Details
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