SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Net Warehouse Interest Income (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Net Warehouse Interest Income
Net warehouse interest income	$ 9,401	$ 6,411	$ 14,896	$ 13,432
Loans Held for Sale
Net Warehouse Interest Income
Warehouse interest income	17,098	12,992	24,501	26,976
Warehouse interest expense	(10,785)	(12,782)	(16,695)	(26,737)
Net warehouse interest income	6,313	210	7,806	239
Loans Held for Investment
Net Warehouse Interest Income
Warehouse interest income	4,763	8,268	11,068	17,047
Warehouse interest expense	(1,675)	(2,067)	(3,978)	(3,854)
Net warehouse interest income	3,088	6,201	7,090	13,193
Secured Borrowings
Net Warehouse Interest Income
Warehouse interest income	849	920	1,695	1,808
Warehouse interest expense	$ (849)	$ (920)	$ (1,695)	$ (1,808)

Interest and fee income generated by loans the Entity intends and has the ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (1) industrial and agricultural; (2) real estate; and (3) real estate construction loans; (4) trade financing; (5) lease financing; (6) home equity lines-of-credit; (7) automobile and other vehicle loans; and (8) credit card and other revolving-type loans. Also includes interest income for leases held by the Entity.

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-SubTopic 220
-Section S99
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Interest and fee income from mortgage loans considered to be held-for-sale.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The net amount of operating interest income (expense).

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Interest income expense net.

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