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, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Revenues	$ 507,640	$ 501,569	$ 1,437,739	$ 1,430,061
Depreciation and amortization	6,221	6,578	18,609	19,397
Income before taxes and noncontrolling interest	24,776	18,597	52,842	57,612
Title segment
Segment Reporting Information [Line Items]
Revenues	493,186	488,612	1,397,722	1,384,857
Depreciation and amortization	5,362	5,534	15,929	16,081
Income before taxes and noncontrolling interest	35,999	24,610	78,860	76,354
Ancillary services and corporate segment
Segment Reporting Information [Line Items]
Revenues	14,454	12,957	40,017	45,204
Depreciation and amortization	859	1,044	2,680	3,316
Income before taxes and noncontrolling interest	$ (11,223)	$ (6,013)	$ (26,018)	$ (18,742)

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 income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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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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