Derivatives and Hedging Activities Derivatives not designated as hedges, effect on statement of operations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Description of Location of Gain (Loss) on Interest Rate Derivative on Income Statement			Other income/ (expense)
Description of Location of Gain (Loss) on Foreign Currency Derivative in Financial Statements			Other income/ (expense)
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ (17)	$ (60)	$ 67	$ 34
Not Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(21)	(60)	62	7
Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ 4	$ 0	$ 5	$ 27