Loans Held for Investment - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Receivables [Abstract]
Loans renegotiated in troubled debt restructurings	$ 6,900,000		$ 6,900,000		$ 14,500,000
Troubled restructurings included in non-accrual loans	4,800,000		4,800,000		11,300,000
Loans renegotiated in troubled debt restructurings, accrual loans	2,100,000		2,100,000		3,200,000
Financing receivable, after allowance for credit loss, noncurrent	100,000		100,000		2,900,000
TDR commitment to lend					$ 0
Troubled debt restructurings	0		0
Charge-offs directly related to modifying troubled debt restructurings	0	$ 0	0	$ 0
Balance of defaulted loans under trouble debt restructurings	0		0
Impaired financing receivable, recorded investment	148,500,000		148,500,000
Commitments to purchase or sell	0	0	0	0
Proceeds from sale of loans held-for-investment	$ 0	$ 0	$ 0	$ 0

Financing Receivable, Modifications, Recorded Investment, Accrual Method

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Financing Receivable, Modifications, Recorded Investment, Non Accrual

+ References

No definition available.

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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-SubTopic 40
-Section 50
-Paragraph 4
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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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- Definition

Reflects the carrying amount of loans and leases for which agreements to acquire or dispose exist.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount, after allowance for credit loss, of accounts and financing receivables, classified as noncurrent. Includes, but is not limited to, notes and loan receivable.

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- Definition

The cash inflow from Sales of Loans Held For Investment.

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