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Common Stock Repurchase Programs - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Aug. 31, 2018
Common Stock [Line Items]
Common stock authorized for repurchase			$ 500.0
Company's Common stock repurchased		$ 98.7
Restricted Stock [Member]
Common Stock [Line Items]
Number of shares withheld to satisfy minimum statutory tax withholding obligations	81,625
Amount withheld to satisfy minimum statutory tax withholding obligations	$ 2.0

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- Definition

Common Stock [Line Items]

+ References

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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

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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