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Common Stock Repurchase Programs - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Aug. 31, 2018
Common Stock [Line Items] |  |  |  |
Common stock authorized for repurchase |  |  |  | $ 500,000
Common stock repurchased | $ 8,493 | $ 145,280 | $ 302,160 |
Company's Common stock repurchased |  |  | $ 107,200 |
Common Stock [Member] |  |  |  |
Common Stock [Line Items] |  |  |  |
Repurchased common stock, shares | 500,000 | 5,100,000 |  |
Restricted Stock [Member] |  |  |  |
Common Stock [Line Items] |  |  |  |
Number of shares withheld to satisfy minimum statutory tax withholding obligations |  | 96,918 |  |
Amount withheld to satisfy minimum statutory tax withholding obligations |  | $ 2,500 |  |

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- Definition Amount of decrease to equity for grantee's tax withholding obligation for award under share-based payment arrangement. + References No definition available. + Details
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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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- Definition Amount remaining of a stock repurchase plan authorized. + References No definition available. + Details
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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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