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

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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 net assets (liabilities).

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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.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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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.

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

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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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Formation of Derivatives Venture (Details) $ in Thousands	3 Months Ended	12 Months Ended
Formation of Derivatives Venture (Details) $ in Thousands	Mar. 31, 2018 USD ($) director	Dec. 31, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Ownership percentage for equity method investments		20.00%
Revenue from Contract with Customer, Including Assessed Tax	$ 131,484
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	$ 249,556	$ 306,051	$ 258,936	$ 318,330
Gain or loss was recognized on investment	0
ITG Derivatives
Revenue from Contract with Customer, Including Assessed Tax		$ 5,300
Matrix Holding Group
Initial investment	2,000
Cash and restricted cash	600
Net assets	$ 1,400