Defined Benefit Pension Plans Schedule of Amounts Recognized in the Consolidated Balance Sheets (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Schedule of Amounts Recognized in the Consolidated Balance Sheets [Line Items]
Plan assets in other long-term assets	$ 481	$ 567
Current portion of pension plan liability in wages and benefits payable	3,833	4,552
Long-term portion of pension plan liability	91,652	101,432
Net pension plan benefit liability	$ 95,004	$ 105,417