Basis of Presentation - Intangible Assets – Activity (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($)
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2019	$ 72,789
Additions	0
Amortization Expense	(8,179)
Carrying Value at June 30, 2020	$ 64,610
Weighted Average Amortization Period (in years)	6 years
5 Arches LLC and CoreVest \| Borrower network
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2019	$ 43,952
Additions	0
Amortization Expense	(3,236)
Carrying Value at June 30, 2020	$ 40,716
Weighted Average Amortization Period (in years)	7 years
5 Arches LLC and CoreVest \| Broker network
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2019	$ 15,083
Additions	0
Amortization Expense	(1,810)
Carrying Value at June 30, 2020	$ 13,273
Weighted Average Amortization Period (in years)	4 years
5 Arches LLC and CoreVest \| Non-compete agreements
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2019	$ 8,236
Additions	0
Amortization Expense	(1,583)
Carrying Value at June 30, 2020	$ 6,653
Weighted Average Amortization Period (in years)	3 years
5 Arches LLC and CoreVest \| Tradenames
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2019	$ 3,472
Additions	0
Amortization Expense	(667)
Carrying Value at June 30, 2020	$ 2,805
Weighted Average Amortization Period (in years)	3 years
5 Arches LLC and CoreVest \| Developed technology
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2019	$ 1,613
Additions	0
Amortization Expense	(450)
Carrying Value at June 30, 2020	$ 1,163
Weighted Average Amortization Period (in years)	2 years
5 Arches LLC and CoreVest \| Loan administration fees on existing loan assets
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2019	$ 433
Additions	0
Amortization Expense	(433)
Carrying Value at June 30, 2020	$ 0

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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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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