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SUBSEQUENT EVENTS (Details) - USD ($) shares in Millions	1 Months Ended
SUBSEQUENT EVENTS (Details) - USD ($) shares in Millions	Jul. 31, 2020	Feb. 29, 2020	Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2019	Jun. 30, 2019	Apr. 30, 2019	Jan. 31, 2019	Oct. 31, 2018	Aug. 31, 2018	Mar. 31, 2018
Subsequent Event
Subsequent Event [Line Items]
Stock repurchased (in shares)	4.8
Stock repurchased, value	$ 31,300,000
Credit facility, maximum borrowing capacity	250,000,000
Consolidated VIEs \| OBX Trust
Subsequent Event [Line Items]
Loans		$ 467,511,000	$ 374,609,000	$ 465,492,000	$ 463,405,000	$ 383,760,000	$ 388,156,000	$ 393,961,000	$ 384,027,000	$ 383,451,000	$ 327,162,000
Consolidated VIEs \| Subsequent Event \| OBX Trust
Subsequent Event [Line Items]
Loans	$ 489,400,000