ITG Acquisition - Assumption of Equity Compensation Plan (Details) - shares	Dec. 31, 2019	Mar. 01, 2019
Assumed Plan \| Class A
Business Acquisition [Line Items]
Shares available for issuance (in shares)	1,230,406	2,497,028

Aggregate number of common shares reserved for future issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant