Debt - Warehouse Lines of Credit (Details) - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Borrowings under warehouse credit facilities	$ 21,987,000	$ 4,733,000
Warehouse Agreement Borrowings
Debt Instrument [Line Items]
Borrowing Capacity as of June 30, 2019	49,000,000
Borrowings under warehouse credit facilities	21,987,000	4,733,000
Western Alliance Bank \| Warehouse Agreement Borrowings
Debt Instrument [Line Items]
Borrowing Capacity as of June 30, 2019	24,500,000
Borrowings under warehouse credit facilities	11,522,000	1,141,000
Texas Capital Bank, N.A. \| Warehouse Agreement Borrowings
Debt Instrument [Line Items]
Borrowing Capacity as of June 30, 2019	24,500,000
Borrowings under warehouse credit facilities	$ 10,465,000	$ 3,592,000

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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=6877327&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=6876686&loc=d3e534808-122878

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