Derivative Financial Instruments Derivative Financial Instruments (Details textual) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Derivative [Line Items]
Net gain (loss)	$ (900,000)	$ (5,000,000)	$ (2,900,000)	$ (3,500,000)
Maturities of foreign currency forward contracts			6 months 0 days
Level 2 | Interest Rate Swap [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Net	1,400,000		1,400,000
Level 2 | Interest Rate Swap [Member] | Other Current Assets
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset	2,400,000		2,400,000
Level 2 | Interest Rate Swap [Member] | Other Current Liabilities
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Liability	$ 1,000,000		$ 1,000,000
Term loan facility [Member]
Derivative [Line Items]
Effective interest rate	2.49%		2.49%