Basis of Condensed Consolidated Financial Statements (Narrative) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Direct premiums and escrow fees	$ 649,726	$ 605,450	$ 1,775,615	$ 1,716,468
Agent premiums	625,953	585,974	1,653,990	1,520,507
Personnel costs	438,692	411,743	1,239,129	1,185,318
Premiums retained by agents	495,130	462,535	1,303,838	1,200,549
Other operating expenses	219,959	209,316	622,995	621,298
Information and other	$ 188,727	173,349	$ 526,575	511,334
Restatement Adjustment | Title Insurance and Services | Closing Protection Letters And Temporary Labor Costs
Segment Reporting Information [Line Items]
Direct premiums and escrow fees		(9,500)		(24,600)
Agent premiums		9,500		24,600
Personnel costs		10,600		29,000
Premiums retained by agents		500		1,200
Other operating expenses		(11,100)		(30,200)
Restatement Adjustment | Title Insurance and Services | Certain Non Risk Revenues
Segment Reporting Information [Line Items]
Direct premiums and escrow fees		(10,700)		(31,500)
Information and other		10,700		31,500
Restatement Adjustment | Specialty Insurance | Closing Protection Letters And Temporary Labor Costs
Segment Reporting Information [Line Items]
Personnel costs		200		700
Other operating expenses		$ (200)		$ (700)