Goodwill (Carrying Amount of Goodwill by Operating Segment) (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($)
Goodwill [Line Items]
Beginning balance	$ 1,017,417
Acquisitions	123,954
Foreign currency translation	4,391
Other adjustments	(298)
Ending balance	1,145,464
Title Insurance and Services
Goodwill [Line Items]
Beginning balance	970,652
Acquisitions	123,954
Foreign currency translation	4,391
Other adjustments	(298)
Ending balance	1,098,699
Specialty Insurance
Goodwill [Line Items]
Beginning balance	46,765
Acquisitions	0
Foreign currency translation	0
Other adjustments	0
Ending balance	$ 46,765

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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