Intangible Assets, Net - Summary of Intangible Assets, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Definite-lived intangible assets:
Investment contracts and other	$ 489,570	$ 489,570
Accumulated amortization	(237,761)	(222,695)
Definite-lived intangible assets, net	251,809	266,875
Indefinite-lived intangible assets	43,516	43,516
Total intangible assets, net	$ 295,325	$ 310,391	$ 325,384	$ 338,812

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

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

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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 assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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