Loans Held for Investment - Narrative (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Receivables [Abstract]
Loans renegotiated in troubled debt restructurings	$ 12,200,000		$ 14,500,000
Troubled restructurings included in non-accrual loans	9,100,000		11,300,000
Loans renegotiated in troubled debt restructurings, accrual loans	3,100,000		3,200,000
Financing receivable, after allowance for credit loss, noncurrent	1,500,000		$ 2,900,000
TDR commitment to lend	0
Troubled debt restructurings	0
Charge-offs directly related to modifying troubled debt restructurings	0
Balance of defaulted loans under trouble debt restructurings	0
Impaired financing receivable, recorded investment	94,400,000
Commitments to purchase or sell	0	$ 0
Proceeds from sale of loans held-for-investment	$ 0	$ 0

Financing Receivable, Modifications, Recorded Investment, Accrual Method

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- Definition

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)
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- Definition

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

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- Definition

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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- Definition

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
-Topic 310
-SubTopic 40
-Section 50
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-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554

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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.

+ References

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- Definition

The cash inflow from Sales of Loans Held For Investment.

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