Derivative Instruments and Hedges (Fair Value Balance Sheet Disclosures) (Details) - Not Designated as Hedging Instrument - Foreign Exchange Contract - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Current derivative assets	$ 2,810	$ 2,489
Noncurrent derivative assets	191	177
Current derivative liabilities	682	284
Noncurrent derivative liabilities	$ 23	$ 56

Fair value, after the effects of master netting arrangements, of a 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, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a 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, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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