Portfolio Loans Receivable - Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 25,252	$ 23,550	$ 25,181	$ 23,434
Provision for (reversal of) off balance sheet credit commitments	2,035	781	2,987	1,284
Ending Balance	26,419	24,079	26,419	24,079
Off Balance Sheet Reserve
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	1,586	1,822	1,736	1,775
Provision for (reversal of) off balance sheet credit commitments	45	(77)	(105)	(30)
Ending Balance	1,631	1,745	1,631	1,745
Mortgage Loan Put-back Reserve
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	1,164	1,284	1,164	1,160
Provision for (reversal of) off balance sheet credit commitments	2	86	2	210
Ending Balance	$ 1,166	$ 1,370	$ 1,166	$ 1,370

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

+ Details

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Balance Type:	debit
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- Details

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- Details

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