Pension, Postretirement and Postemployment Benefits (Details 2) (Pension Benefits, USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Pension, Postretirement and Postemployment Benefits
Fair Value of Plan assets	$ 21,384	$ 18,780	$ 16,352
Cash
Pension, Postretirement and Postemployment Benefits
Fair Value of Plan assets	558
Available-for-sale equity securities
Pension, Postretirement and Postemployment Benefits
Fair Value of Plan assets	11,988
Available-for-sale debt securities
Pension, Postretirement and Postemployment Benefits
Fair Value of Plan assets	8,838
Total Short-term investments
Pension, Postretirement and Postemployment Benefits
Fair Value of Plan assets	20,826
Level 2
Pension, Postretirement and Postemployment Benefits
Fair Value of Plan assets	21,384
Level 2 | Cash
Pension, Postretirement and Postemployment Benefits
Fair Value of Plan assets	558
Level 2 | Available-for-sale equity securities
Pension, Postretirement and Postemployment Benefits
Fair Value of Plan assets	11,988
Level 2 | Available-for-sale debt securities
Pension, Postretirement and Postemployment Benefits
Fair Value of Plan assets	8,838
Level 2 | Total Short-term investments
Pension, Postretirement and Postemployment Benefits
Fair Value of Plan assets	$ 20,826