Investment Securities - SEREF (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2012	Dec. 31, 2020
Residential Real Estate
Fair value of the investment	$ 29,772		$ 45,336
SEREF
Residential Real Estate
Number of shares acquired		9,140,000
Fair value of the investment	$ 10,700		$ 11,200
Ownership percentage	2.00%

Represents the number of shares acquired in the equity security investment.

No definition available.

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- Definition

Represents the percentage ownership in the equity security investment.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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