Employee Benefit Plans (Details 4) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Amounts applicable to the Company's defined benefit plans with accumulated benefit obligations in excess of plan assets
Projected benefit obligation	$ 5,832	$ 7,112
Accumulated benefit obligation	$ 5,832	$ 7,112

Amount of accumulated benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2417-114920

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant