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	12 Months Ended
	Dec. 31, 2018 USD ($) Contract	Dec. 31, 2017 USD ($) Contract	Dec. 31, 2016 USD ($)	Dec. 31, 2017 JPY (¥) Contract
Foreign Currency Derivatives [Abstract]
Unrealized gains/(losses) related to foreign currency cash flow hedges included in accumulated other comprehensive loss	$ 0	$ 100
Cumulative translation adjustments included in accumulated other comprehensive loss	$ (79,900)	$ (66,400)	$ (84,700)
Foreign Currency Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member]
Foreign Currency Derivatives [Abstract]
Number of contracts \| Contract	0	0		0
Foreign Currency Forward Contracts [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedges [Member]
Foreign Currency Derivatives [Abstract]
Number of contracts \| Contract	0
Notional amount		$ 5,500		¥ 600.0
Fair value	$ 0	200
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	(160)	(152)	(1,423)
Foreign Currency Forward Contracts [Member] \| Other Income (Expense) [Member] \| Not Designated as Hedging Instrument [Member]
Foreign Currency Derivatives [Abstract]
Gain (loss) recognized in income	0	(485)	39
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	18	119	(1,088)
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	$ 358	$ (1,544)