Segment information - Selected Statement of Operations and Income (Loss) Information Related to Segments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Revenues	$ 472,075	$ 492,869	$ 870,595	$ 930,099
Depreciation and amortization	5,775	6,154	11,764	12,388
Income (loss) before taxes and noncontrolling interest	29,352	31,321	22,126	28,066
Title segment
Segment Reporting Information [Line Items]
Revenues	463,636	479,125	848,074	904,536
Depreciation and amortization	5,048	5,249	10,200	10,566
Income (loss) before taxes and noncontrolling interest	39,041	37,737	38,661	42,862
Ancillary services and corporate segment
Segment Reporting Information [Line Items]
Revenues	8,439	13,744	22,521	25,563
Depreciation and amortization	727	905	1,564	1,822
Income (loss) before taxes and noncontrolling interest	$ (9,689)	$ (6,416)	$ (16,535)	$ (14,796)

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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