Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Fair value as of the balance sheet date of all foreign currency derivative assets designated as cash flow hedging instruments.

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Fair value as of the balance sheet date of all foreign currency derivative liabilities designated as cash flow hedging instruments.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Accumulated Other Comprehensive Income (Details) $ in Thousands, € in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 EUR (€)	May 31, 2018 EUR (€)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 EUR (€)	Nov. 30, 2016 EUR (€)
Components of comprehensive income
Net income	$ 4,554	$ 5,667	$ 15,454	$ 15,565
Mark to market of foreign exchange hedges	(31)	92	(147)	532
Deferred income tax (expense) benefit	7	(34)	34	(195)
Comprehensive income	4,530	$ 5,725	15,341	$ 15,902
Foreign exchange hedges assets							$ 111
Foreign exchange hedges liabilities	35		35
Prepaid expenses and other current assets
Components of comprehensive income
Foreign exchange hedges assets							83
Other assets, net
Components of comprehensive income
Foreign exchange hedges assets	8		8				$ 28
Accrued Expenses
Components of comprehensive income
Foreign exchange hedges liabilities	$ 43		$ 43
Foreign Exchange Contract
Components of comprehensive income
Foreign exchange hedges liabilities \| €					€ 0.7
Foreign Exchange Contract \| Designated as Hedging Instrument
Components of comprehensive income
Notional amount \| €					€ 2.9	€ 2.2		€ 2.2	€ 5.5