For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fair value, after effects of master netting arrangements, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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-Publisher FASB
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- Definition

The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
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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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No definition available.

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Financial Instruments (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Offsetting Assets [Line Items]
Margin Deposit Assets	$ 3,900		$ 3,600
Derivative Asset, Fair Value, Amount Offset Against Collateral	2,500		$ 2,300
Revenue, Net	456,100	$ 314,851
Largest Customer [Member] \| Customer Concentration Risk [Member] \| Sales Revenue, Net [Member]
Offsetting Assets [Line Items]
Revenue, Net	$ 123,200
Largest Customer [Member] \| Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Offsetting Assets [Line Items]
Concentration Risk, Percentage	34.00%