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VARIABLE INTEREST ENTITIES - Schedule of the Fair Value of OBX Trusts Closed (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Sep. 30, 2020 | 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
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OBX Trust | Consolidated VIEs |  |  |  |  |  |  |  |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Loans | $ 257,135 | $ 514,609 | $ 489,352 | $ 467,511 | $ 374,609 | $ 465,492 | $ 463,405 | $ 383,760 | $ 388,156 | $ 393,961 | $ 384,027 | $ 383,451 | $ 327,162

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- Definition Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 310 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-29(Column G)) -URI http://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014 + Details
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