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

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Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Derivative Financial Instruments (Details) $ in Thousands, ¥ in Billions	3 Months Ended
	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2018 JPY (¥)
Foreign Currency Derivatives [Abstract]
Unrealized gains/(losses) related to foreign currency cash flow hedges included in accumulated other comprehensive loss	$ 0		$ 0
Cumulative translation adjustments included in accumulated other comprehensive loss	75,800		$ 79,900
Foreign Currency Forward Contracts [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedges [Member]
Foreign Currency Derivatives [Abstract]
Notional amount	0
Fair value	0	$ 100
Foreign Currency Forward Contracts [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedges [Member] \| Japanese Yen [Member]
Foreign Currency Derivatives [Abstract]
Notional amount		2,800		¥ 0.3
Foreign Currency Forward Contracts [Member] \| Other Comprehensive Income (Loss) [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedges [Member]
Foreign Currency Derivatives [Abstract]
Gain (loss) recognized in other comprehensive loss	0	(247)
Foreign Currency Forward Contracts [Member] \| Other Income (Expense) [Member] \| Not Designated as Hedging Instrument [Member] \| Fair Value Hedges [Member]
Foreign Currency Derivatives [Abstract]
Gain (loss) recognized in income	0	0
Foreign Currency Forward Contracts [Member] \| Revenue [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedges [Member]
Foreign Currency Derivatives [Abstract]
Gain (loss) reclassified from accumulated other comprehensive loss into income	0	(49)
Foreign Currency Forward Contracts [Member] \| Selling Expenses [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedges [Member]
Foreign Currency Derivatives [Abstract]
Gain (loss) reclassified from accumulated other comprehensive loss into income	$ 0	$ 0