Number of directors in the board of directors of Matrix appointed by the company.

No definition available.

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- Definition

Number of directors in the board of directors of Matrix appointed by Optech.

+ References

No definition available.

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- Definition

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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- Definition

Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

+ References

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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- Definition

The amount of assets reported by an equity method investment of the entity.

+ References

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The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

+ References

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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Equity Investment (Details) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Equity Investment (Details) $ in Thousands	Jun. 30, 2018 USD ($)	Jun. 30, 2018 USD ($) director	Dec. 31, 2017 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Ownership percentage for equity method investments			20.00%
Revenues	$ 128,477	$ 259,961
Number of directors in the board of directors of Matrix appointed by Optech \| director		2
Number of directors in the board of directors of Matrix appointed by the company \| director		1
Cash and restricted cash	254,709	$ 254,709	$ 306,051	$ 268,945	$ 318,330
Gain or loss was recognized on investment	0	0
Legal Fees	200	200
ITG Derivatives
Revenues			$ 5,300
Matrix Holding Group
Initial investment	2,000	2,000
Matrix Holding Group \| Cash and restricted cash
Initial investment	600	600
Matrix Holding Group \| Non-cash assets
Initial investment	$ 1,400	$ 1,400