SERVICING - (Detail) - USD ($) $ in Billions	Jun. 30, 2018	Dec. 31, 2017
Loans serviced
Servicing
Servicing portfolio loans unpaid principal balance	$ 77.8	$ 74.3

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=82924980&loc=d3e107314-111719

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