OFFSETTING ASSETS AND LIABILITIES - SCHEDULE OF ASSETS AND LIABILITIES SUBJECT TO MASTER NETTING ARRANGEMENTS (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets
Gross amount of securities borrowed	$ 879	$ 372
Gross amount offset on the unaudited condensed consolidated balance sheets	0	0
Amounts of assets presented on the unaudited condensed consolidated balance sheets	879	372
Securities borrowed	879	372
Security collateral received	(816)	(361)
Net amount	63	11
Liabilities
Gross amount of securities loaned	3,129,650	1,921,118
Gross amount of securities loaned offset on the unaudited condensed consolidated balance sheets	0	0
Amounts of liabilities presented on the unaudited condensed consolidated balance sheets	3,129,650	1,921,118
Securities loaned	3,129,650	1,921,118
Security collateral pledged	(3,017,536)	(1,787,819)
Net amount	$ 112,114	$ 133,299

Amount, after the effects of master netting arrangements, of securities borrowed from entities in exchange for collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against securities borrowed.

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