Discontinued operations - Schedule of Gain (Loss) on Disposal Activity (Detail) - Red Violet, Inc. - Discontinued Operations, Disposed of $ in Thousands	6 Months Ended
Jun. 30, 2018 USD ($)
Loss On Disposal Of Discontinued Operations [Line Items]
Share-based compensation expense	$ 15,548
Write-off of unamortized debt costs	284
Write-off of certain prepaid expenses	198
Spin-off related professional fees	2,012
Spin-off related employee compensation	998
Loss on disposal of discontinued operations	$ 19,040

Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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