Related Person Transactions - TRMT 2019 Offering (Details) - USD ($) $ / shares in Units, $ in Thousands	May 21, 2019	Sep. 30, 2020
TRMT \| Tremont Advisors
Related Party Transaction [Line Items]
Number of shares owned (in shares)		1,600,100
Ownership percentage		19.30%
Common shares \| TRMT \| Underwritten Public Offering
Related Party Transaction [Line Items]
Number of shares issued (in shares)	5,000,000
Common stock, par value (in dollars per share)	$ 0.01
Share purchase from related party (in shares)	1,000,000
Purchase from related party	$ 5,650

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Related Party Transaction, Purchases From Related Party, Shares

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Face amount or stated value per share of common stock.

+ References

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-Publisher FASB
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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