Fair Value Measurements (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Asset derivatives	$ 1,195	$ 397
Liability derivatives	(285)	(1,754)
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	2,341	2,216
Financial assets and financial liabilities, reported at fair value	2,341	2,216
Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Asset derivatives	1,195	397
Liability derivatives	(285)	(1,754)
Bank acceptances	9,999	9,690
Rabbi trust assets	0	0
Financial assets and financial liabilities, reported at fair value	10,909	8,333
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	1,195	397
Liability derivatives	(285)	(1,754)
Bank acceptances	9,999	9,690
Rabbi trust assets	2,341	2,216
Financial assets and financial liabilities, reported at fair value	$ 13,250	$ 10,549
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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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 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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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.

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Fair value of asset after deduction of liability.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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