XML 21 R31.htm IDEA: XBRL DOCUMENT v2.4.0.6
Derivative Instruments (Details 1) (Hedge asset [Member], USD $)
In Thousands, unless otherwise specified
Jun. 30, 2012
Dec. 31, 2011
Hedge asset [Member]
   
Effect of Cash Flow Hedges on the Consolidated Balance Sheet    
Asset fair value $ 4,814 $ 6,418