SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Contracts with Customers (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Contracts with Customers
Revenue from contracts with customer	$ 36,412	$ 20,492
Loan Origination Fees \| Gains from Mortgage Banking Activities
Contracts with Customers
Revenue from contracts with customer	21,348	11,531
Investment Sales Broker Fees, Investment Management Fees, Assumption Fees, Application Fees and Other \| Other Revenues
Contracts with Customers
Revenue from contracts with customer	$ 15,064	$ 8,961

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration