Derivative Financial Instruments Derivative Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Derivative, Notional Amount	$ 120,253	$ 119,008
Swedish kronor
Derivative, Notional Amount	62,499	67,809
British pound sterling
Derivative, Notional Amount	17,644	14,928
Australian dollar
Derivative, Notional Amount	3,098	6,566
Japanese yen
Derivative, Notional Amount	3,572	3,718
Euro
Derivative, Notional Amount	6,498	5,391
Canada, Dollars
Derivative, Notional Amount	20,602	17,446
Other
Derivative, Notional Amount	$ 6,340	$ 3,150