Goodwill and Other Intangible Assets, Net - Summary of Changes in Carrying Amount of Goodwill by Reportable Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Beginning balance	$ 392,570	$ 163,339
Acquisitions	581,518	232,540
Divestitures	(163,300)
Measurement period adjustments	4,822	(869)
Cumulative translation adjustment	(3,844)	(2,440)
Ending balance	811,766	392,570
Financial Services [Member]
Goodwill [Line Items]
Beginning balance	134,898	85,163
Acquisitions	453,833	51,952
Divestitures	(163,300)
Measurement period adjustments	(2,658)	223
Cumulative translation adjustment	(3,844)	(2,440)
Ending balance	418,929	134,898
Real Estate Services [Member]
Goodwill [Line Items]
Beginning balance	257,672	78,176
Acquisitions	127,685	180,588
Measurement period adjustments	7,480	(1,092)
Ending balance	$ 392,837	$ 257,672

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
-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
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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 350
-SubTopic 20
-Section 50
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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