Servicing - Additional Information (Detail) - USD ($) $ in Billions	Jun. 30, 2016	Dec. 31, 2015
Loans serviced
Servicing
Unpaid principal balance of loans serviced	$ 57.3	$ 50.2
HUD Loan Portfolio Acquired
Servicing
Unpaid principal balance of loans serviced	$ 3.8

This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51814546&loc=d3e107314-111719

Name:	us-gaap_PrincipalAmountOutstandingOnLoansManagedAndSecuritized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant