Employee Benefit Plans (Details Textual) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Postretirement Benefits [Line Items]
Contributions to the defined contribution plans	$ 1,900,000	$ 1,100,000	$ 900,000
Funded status of the Pension Plans	(2,898,000)	1,546,000
Funded status of the pension plans to other comprehensive income (loss), net of income taxes	(3,700,000)	4,800,000	(400,000)
Estimated contributions to pension plans	600,000
Projected benefit obligation	29,266,000	24,036,000	28,357,000
Other Noncurrent Liabilities [Member]
Postretirement Benefits [Line Items]
Funded status of the Pension Plans	(2,899,000)
Other Noncurrent Assets [Member]
Postretirement Benefits [Line Items]
Funded status of the Pension Plans		1,546,000
Postretirement Health Coverage [Member] \| Other Noncurrent Liabilities [Member]
Postretirement Benefits [Line Items]
Projected benefit obligation	$ 1,700,000	$ 1,600,000

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1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

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-Publisher FASB

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans, attributable to parent entity.

+ References

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