Fair Value Measurements (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Asset derivatives	$ 685	$ 699
Liability derivatives	(1,681)	(458)
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Asset derivatives	0	0
Liability derivatives	0	0
Bank acceptances	0	0
Rabbi trust assets	2,176	2,159
Financial assets and financial liabilities, reported at fair value	2,176	2,159
Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Asset derivatives	685	699
Liability derivatives	(1,681)	(458)
Bank acceptances	8,660	10,823
Rabbi trust assets	0	0
Financial assets and financial liabilities, reported at fair value	7,664	11,064
Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Asset derivatives	0	0
Liability derivatives	0	0
Bank acceptances	0	0
Rabbi trust assets	0	0
Financial assets and financial liabilities, reported at fair value	0	0
Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Asset derivatives	685	699
Liability derivatives	(1,681)	(458)
Bank acceptances	8,660	10,823
Rabbi trust assets	2,176	2,159
Financial assets and financial liabilities, reported at fair value	$ 9,840	$ 13,223
Minimum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Maturity of bank acceptances	3 months
Maximum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Maturity of bank acceptances	6 months

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- Definition

The fair values as of the Balance Sheet date of Rabbi Trust Assets.

+ References

No definition available.

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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. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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Fair value, after the effects of master netting arrangements, of a financial liability or 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. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Amounts receivable from customers on short-term negotiable time drafts drawn on and accepted by the institution (also known as banker's acceptance transactions) that are outstanding on the reporting date.

+ References

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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.

+ References

No definition available.

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Fair value of asset after deduction of liability.

+ References

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