Retirement Pension Plan - Schedule of Pension Liability Adjustments Recognized in Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Compensation and Retirement Disclosure [Abstract]
Amortization of unrecognized actuarial loss	$ 227	$ 145	$ 131
Current deferral of gains	(1,377)	214	393
Pension liability adjustments recognized in comprehensive income	(1,150)	359	524
Tax effect	391	(122)	(178)
Net pension liability adjustments	$ (759)	$ 237	$ 346

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The amount of gains or losses recognized in net periodic benefit cost.

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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.

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

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Amount before tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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

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