Quarterly report pursuant to Section 13 or 15(d)

Derivatives (Details 2)

Derivatives (Details 2) (Interest rate swaps (Swaps), Cash flow hedge, USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Interest rate swaps (Swaps) | Cash flow hedge
Impact of the Swap on the consolidated financial statements    
Effective portion of gain (loss) recognized in Accumulated other comprehensive loss $ (909) $ (2,503)
Effective portion of gain (loss) reclassified from Accumulated other comprehensive loss into Net income (1,168) (98)
Ineffective portion of amount of gain (loss) recognized into Net income on interest rate swaps $ 19