GUARANTY OBLIGATION AND ALLOWANCE FOR RISK-SHARING OBLIGATIONS - Summary of Allowance for Risk-Sharing Obligations (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Allowance for Risk-Sharing Contracts
Beginning balance	$ 3,546	$ 5,149	$ 3,613	$ 5,586
Provision (benefit) for risk-sharing obligations	122	275	(35)	121
Other	(20)	386	70	103
Ending balance	3,648	$ 5,810	3,648	$ 5,810
Fannie Mae DUS program
Allowance for Risk-Sharing Contracts
Maximum quantifiable contingent liability associated with guarantees	$ 5,300,000		$ 5,300,000

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

+ References

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

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