Discontinued operations - Disposal of Discontinued Activity (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Major classes of line items constituting loss from discontinued operations:
Loss from operations of discontinued operations, net of $0 income taxes	$ (12,133)	$ (2,084)	$ (15,026)
Loss on disposal of discontinued operations, net of $0 income taxes		(19,040)
Net loss from discontinued operations	(12,133)	(21,124)	(15,026)
Discontinued Operations, Disposed of [Member] \| Red Violet, Inc. [Member]
Major classes of line items constituting loss from discontinued operations:
Revenue	1,993	3,325	3,565
Cost of revenue (exclusive of depreciation and amortization)	1,843	2,017	3,244
Sales and marketing expenses	1,165	1,089	1,983
General and administrative expenses	10,898	1,852	12,928
Depreciation and amortization	220	451	436
Loss from operations of discontinued operations, net of $0 income taxes	(12,133)	(2,084)	(15,026)
Loss on disposal of discontinued operations, net of $0 income taxes		(19,040)
Net loss from discontinued operations	$ (12,133)	$ (21,124)	$ (15,026)

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

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Amount after tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until disposal.

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