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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Basis of Presentation - Intangible Assets – Activity (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Finite-lived Intangible Assets [Roll Forward]
Amortization Expense	$ 1,900	$ 0	$ 2,532	$ 0
5 Arches, LLC
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2018			0
Additions			24,800
Amortization Expense			(2,529)
Carrying Value at June 30, 2019	22,271		$ 22,271
Weighted Average Amortization Period (in years)			4 years
5 Arches, LLC \| Broker network
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2018			$ 0
Additions			18,100
Amortization Expense			(1,207)
Carrying Value at June 30, 2019	16,893		$ 16,893
Weighted Average Amortization Period (in years)			5 years
5 Arches, LLC \| Non-compete agreements
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2018			$ 0
Additions			2,900
Amortization Expense			(322)
Carrying Value at June 30, 2019	2,578		$ 2,578
Weighted Average Amortization Period (in years)			3 years
5 Arches, LLC \| Management fee on existing assets under management
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2018			$ 0
Additions			2,600
Amortization Expense			(867)
Carrying Value at June 30, 2019	1,733		$ 1,733
Weighted Average Amortization Period (in years)			1 year
5 Arches, LLC \| Tradename
Finite-lived Intangible Assets [Roll Forward]
Carrying Value at December 31, 2018			$ 0
Additions			1,200
Amortization Expense			(133)
Carrying Value at June 30, 2019	$ 1,067		$ 1,067
Weighted Average Amortization Period (in years)			3 years