SIGNIFICANT ACCOUNTING POLICIES - Securities Sold Under Agreements to Repurchase (Details) $ in Thousands, $ in Thousands	Dec. 31, 2020 HKD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 HKD ($)
SIGNIFICANT ACCOUNTING POLICIES
Assets Sold under Agreements to Repurchase, Carrying Amount	$ 5,453,037	$ 703,309	$ 1,590

Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(i)(A)(i))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant