Basis of Presentation - Intangible Assets – Activity (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	81,300
Amortization Expense	(8,511)
Carrying Value at December 31, 2019	$ 72,789
Weighted Average Amortization Period (in years)	6 years
5 Arches, LLC
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	24,800
Amortization Expense	(6,323)
Carrying Value at December 31, 2019	$ 18,477
Weighted Average Amortization Period (in years)	5 years
CoreVest LLC
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	56,500
Amortization Expense	(2,188)
Carrying Value at December 31, 2019	$ 54,312
Weighted Average Amortization Period (in years)	6 years
Broker network \| 5 Arches, LLC
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	18,100
Amortization Expense	(3,017)
Carrying Value at December 31, 2019	$ 15,083
Weighted Average Amortization Period (in years)	5 years
Borrower network \| CoreVest LLC
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	45,300
Amortization Expense	(1,348)
Carrying Value at December 31, 2019	$ 43,952
Weighted Average Amortization Period (in years)	7 years
Non-compete agreements \| 5 Arches, LLC
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	2,900
Amortization Expense	(806)
Carrying Value at December 31, 2019	$ 2,094
Weighted Average Amortization Period (in years)	3 years
Non-compete agreements \| CoreVest LLC
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	6,600
Amortization Expense	(458)
Carrying Value at December 31, 2019	$ 6,142
Weighted Average Amortization Period (in years)	3 years
Loan administration fees on existing loan assets \| 5 Arches, LLC
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	2,600
Amortization Expense	(2,167)
Carrying Value at December 31, 2019	$ 433
Weighted Average Amortization Period (in years)	1 year
Tradename \| 5 Arches, LLC
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	1,200
Amortization Expense	(333)
Carrying Value at December 31, 2019	$ 867
Weighted Average Amortization Period (in years)	3 years
Tradename \| CoreVest LLC
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	2,800
Amortization Expense	(194)
Carrying Value at December 31, 2019	$ 2,606
Weighted Average Amortization Period (in years)	3 years
Developed technology \| CoreVest LLC
Finite-Lived Intangible Assets [Line Items]
Carrying Value at December 31, 2018	$ 0
Additions	1,800
Amortization Expense	(188)
Carrying Value at December 31, 2019	$ 1,612
Weighted Average Amortization Period (in years)	2 years

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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