Debt - Warehouse Lines of Credit (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Outstanding Borrowings	$ 39,825,000	$ 39,029,000
Warehouse Agreement Borrowings
Debt Instrument [Line Items]
Borrowing Capacity	105,000,000	105,000,000
Outstanding Borrowings	$ 39,825,000	$ 39,029,000
Weighted-Average Interest Rate on Outstanding Borrowings	0.00%	0.00%
Western Alliance Bank \| Warehouse Agreement Borrowings
Debt Instrument [Line Items]
Borrowing Capacity	$ 50,000,000	$ 50,000,000
Outstanding Borrowings	$ 16,369,000	$ 18,277,000
Weighted-Average Interest Rate on Outstanding Borrowings	3.25%	3.25%
Texas Capital Bank, N.A. \| Warehouse Agreement Borrowings
Debt Instrument [Line Items]
Borrowing Capacity	$ 40,000,000	$ 40,000,000
Outstanding Borrowings	$ 15,674,000	$ 12,903,000
Weighted-Average Interest Rate on Outstanding Borrowings	2.98%	3.35%
Flagstar Bank, FSB \| Warehouse Agreement Borrowings
Debt Instrument [Line Items]
Borrowing Capacity	$ 15,000,000	$ 15,000,000
Outstanding Borrowings	$ 7,782,000	$ 7,849,000
Weighted-Average Interest Rate on Outstanding Borrowings	3.00%	3.00%

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.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Carrying value as of the balance sheet date of the outstanding short-term borrowings under a revolving line of credit used by mortgage bankers to finance the origination or purchase of loans.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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