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Net Loss per Share - Additional Information (Detail) - shares | 3 Months Ended
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Mar. 31, 2019 | Mar. 31, 2018
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] |  |
Redeemable common stock | 1,717,808 | 457,971
Redeemable Common Stock [Member] |  |
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] |  |
Redeemable common stock | 107,371 | 107,371

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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. + References No definition available. + Details
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- Definition Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS). + References No definition available. + Details
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- Details
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