GUARANTY OBLIGATION AND ALLOWANCE FOR RISK-SHARING OBLIGATIONS - Summary of Allowance for Risk-Sharing Obligations (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Allowance for Risk-Sharing Contracts
Beginning balance	$ 3,613	$ 5,586
Provision (benefit) for risk-sharing obligations	(157)	(154)
Other	90	(283)
Ending balance	3,546	$ 5,149
Fannie Mae DUS program
Allowance for Risk-Sharing Contracts
Maximum quantifiable contingent liability associated with guarantees	$ 5,200,000

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of expense related to credit loss from transactions other than loan and lease transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(11))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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- Definition

Amount of allowance to cover probable credit losses on loans under the Company's risk-sharing obligations with Fannie Mae.

+ References

No definition available.

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- Definition

The increase (decrease) in the allowance for risk-sharing obligations due to other factors.

+ References

No definition available.

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