Amount of assets disposed in disposal including discontinued operation.

No definition available.

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- Definition

Amount of direct selling costs paid or payable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

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.

+ References

No definition available.

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Divestitures - ITG Investment Research, LLC (Details) - USD ($)		12 Months Ended
	May 27, 2016	Dec. 31, 2018	Dec. 31, 2016
Divestitures
Pre-tax gain on sale		$ 608,000
After-tax gain on sale of business			$ 21,000
ITG Investment Research \| Sale of subsidiaries
Divestitures
Cash proceeds from sale	$ 12,000,000
Carrying value of net assets disposed	(7,502,000)
Direct selling costs	(4,477,000)
Pre-tax gain on sale	$ 21,000
After-tax gain on sale of business		$ 50,000