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, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Revenues	$ 818,809	$ 516,105	$ 1,507,395	$ 956,005
Depreciation and amortization	6,819	4,061	13,249	8,292
Income (loss) before taxes	129,456	49,020	203,458	58,289
Title segment
Segment Reporting Information [Line Items]
Revenues	753,119	504,436	1,385,704	938,875
Depreciation and amortization	4,709	3,733	9,022	7,554
Income (loss) before taxes	125,671	54,795	202,761	69,629
Ancillary services and corporate segment
Segment Reporting Information [Line Items]
Revenues	65,690	11,669	121,691	17,130
Depreciation and amortization	2,110	328	4,227	738
Income (loss) before taxes	$ 3,785	$ (5,775)	$ 697	$ (11,340)