Discontinued operations - Disposal of Discontinued Activity (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Major classes of line items constituting loss from discontinued operations:
Loss from operations of discontinued operations, net of $0 income taxes	$ 0	$ (3,334)	$ (2,084)	$ (18,360)
Loss on disposal of discontinued operations, net of $0 income taxes	0	0	(19,040)	0
Net loss from discontinued operations	0	(3,334)	(21,124)	(18,360)
Discontinued Operations, Disposed of \| Red Violet, Inc.
Major classes of line items constituting loss from discontinued operations:
Revenue	0	2,306	3,325	5,871
Cost of revenue (exclusive of depreciation and amortization)	0	1,955	2,017	5,199
Sales and marketing expenses	0	1,175	1,089	3,158
General and administrative expenses	0	2,222	1,852	15,150
Depreciation and amortization	0	288	451	724
Loss from operations of discontinued operations, net of $0 income taxes	0	(3,334)	(2,084)	(18,360)
Loss on disposal of discontinued operations, net of $0 income taxes	0	0	(19,040)	0
Net loss from discontinued operations	$ 0	$ (3,334)	$ (21,124)	$ (18,360)

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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