Share Repurchase Program - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions |
9 Months Ended | ||
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Sep. 30, 2018 |
Feb. 06, 2018 |
Dec. 31, 2017 |
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| Class of Stock [Line Items] | |||
| Stock repurchase program expiration date | Feb. 06, 2021 | ||
| Class A Common Stock [Member] | |||
| Class of Stock [Line Items] | |||
| Common Stock, par value | $ 0.001 | $ 0.001 | |
| Stock repurchase program authorized amount | $ 150.0 | ||
| Class A Common Stock [Member] | Share Repurchase Program [Member] | |||
| Class of Stock [Line Items] | |||
| Common Stock, par value | $ 0.001 | ||
| Stock repurchase program remaining authorized repurchase amount | $ 92.0 |
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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. No definition available.
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- Definition Face amount or stated value per share of common stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of stock repurchase plan authorized. No definition available.
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- Definition Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format. No definition available.
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- Definition Amount remaining of a stock repurchase plan authorized. No definition available.
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- Details
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- Details
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