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, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Revenues	$ 492,869	$ 485,452	$ 930,099	$ 928,493
Depreciation and amortization	6,154	6,441	12,388	12,819
Income before taxes and noncontrolling interest	31,321	33,147	28,066	39,015
Title segment
Segment Reporting Information [Line Items]
Revenues	479,125	470,449	904,536	896,246
Depreciation and amortization	5,249	5,321	10,566	10,547
Income before taxes and noncontrolling interest	37,737	39,467	42,862	51,744
Ancillary services and corporate segment
Segment Reporting Information [Line Items]
Revenues	13,744	15,003	25,563	32,247
Depreciation and amortization	905	1,120	1,822	2,272
Income before taxes and noncontrolling interest	$ (6,416)	$ (6,320)	$ (14,796)	$ (12,729)

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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