Fair Value of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities carried at fair value	$ 14,195	$ 16,751
Derivatives not designated as hedges [Member] | Fair Value, Inputs, Level 2 [Member] | Cross-currency swap agreement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities carried at fair value	$ 7,170	$ 7,632