Goodwill and Other Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Unamortizable intangible assets	$ 176,255	$ 180,343
Gross Carrying Amount, Amortizable intangible assets	2,006,457	1,859,362
Gross Carrying Amount, Total intangible assets	2,182,712	2,039,705
Accumulated Amortization, Amortizable intangible assets	(771,673)	(589,236)
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Amortizable intangible assets	761,290	746,814
Accumulated Amortization, Amortizable intangible assets	(270,447)	(195,056)
Mortgage servicing rights [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Amortizable intangible assets	501,087	377,995
Accumulated Amortization, Amortizable intangible assets	(180,563)	(133,272)
Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Amortizable intangible assets	306,559	320,306
Accumulated Amortization, Amortizable intangible assets	(46,837)	(38,581)
Management contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Unamortizable intangible assets	101,355	103,143
Gross Carrying Amount, Amortizable intangible assets	177,014	180,099
Accumulated Amortization, Amortizable intangible assets	(99,733)	(87,687)
Non-compete agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Amortizable intangible assets	73,750	73,750
Accumulated Amortization, Amortizable intangible assets	(32,777)	(8,194)
Backlog and incentive fees [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Amortizable intangible assets	48,445	49,667
Accumulated Amortization, Amortizable intangible assets	(48,445)	(49,667)
Other amortizable intangible assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Amortizable intangible assets	138,312	110,731
Accumulated Amortization, Amortizable intangible assets	(92,871)	(76,779)
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Unamortizable intangible assets	56,800	56,800
Trade names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Unamortizable intangible assets	$ 18,100	$ 20,400

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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