Pension and Other Postretirement Benefits (Details 13) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Multiemployer Plans [Line Items]
Zone status based on funding, percent, red zone	65.00%
Zone status based on funding, percent, yellow zone	80.00%
Zone status based on funding, percent, green zone	80.00%
Contributions by the Company	$ 393		$ 386		$ 362
Multi-employer pension plan [Member] | Teamsters Local 641 Pension Fund [Member]
Multiemployer Plans [Line Items]
Contributions by the Company	101	[1]	106	[1]	103	[1]
Multiemployer Plans, Increase In Required Contributions, Estimate	4.00%
Multi-employer pension plan [Member] | Swedish Pension Plan (ITP) (B) [Member]
Multiemployer Plans [Line Items]
Contributions by the Company	292	[2]	280	[2]	259	[2]
Multi-employer post-retirement benefit plan [Member]
Multiemployer Plans [Line Items]
Contributions by the Company	$ 202		$ 238		$ 233

[1] Plan information is publicly available for the Local 641 Pension fund. The Form 5500 indicates that the Plan is currently underfunded. Future contributions have increased pursuant to the collective bargaining agreement (dated January 31, 2011 and expiring on January 31, 2014) and the updated Rehabilitation Plan (dated February 17, 2011). Per the terms of the Rehabilitation Plan, required contributions will increase by approximately 4% (annually) through 2018.

[2] The Company also contributes to a Swedish pension plan that supplements the Swedish social insurance system. The pension plan guarantees employees a pension based on a percentage of their salary and also represents a multi-employer pension plan, however the pension plan was not significant in any year presented. This pension plan is not underfunded.