Segment information - Selected Statement of Operations and Income (Loss) Information Related to Segments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Revenues	$ 559,508	$ 507,640	$ 1,430,102	$ 1,437,739
Depreciation and amortization	5,694	6,221	17,458	18,609
Income before taxes and noncontrolling interests	91,061	24,775	113,187	52,842
Title segment
Segment Reporting Information [Line Items]
Revenues	501,199	493,186	1,349,272	1,397,722
Depreciation and amortization	5,110	5,362	15,309	15,929
Income before taxes and noncontrolling interests	49,481	35,999	88,144	78,860
Ancillary services and corporate segment
Segment Reporting Information [Line Items]
Revenues	58,309	14,454	80,830	40,017
Depreciation and amortization	584	859	2,149	2,680
Income before taxes and noncontrolling interests	$ 41,580	$ (11,224)	$ 25,043	$ (26,018)

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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