Quarterly Financial Data - Condensed Consolidated Statement of Operations (Parenthetical) (Detail) - USD ($) |
3 Months Ended | ||
---|---|---|---|
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
|
Quarterly Financial Information [Line Items] | |||
Reclassification of operating expense to change in fair value of contingent consideration | $ 1,100,000 | ||
Maximum [Member] | |||
Quarterly Financial Information [Line Items] | |||
Reclassification of net income (loss) from discontinued operations to continuing operations | $ 10,000 | $ 10,000 | $ 10,000 |