v2.4.0.6
Long-Term Debt (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2011
Oct. 21, 2011
Line of Credit Facility    
Stand-by letters of credit $ (294)  
Maximum additional available borrowing amount 103,206  
Senior Unsecured Revolving Credit Facility [Member]
   
Line of Credit Facility    
Maximum aggregate available borrowing amount 250,000 250,000
Outstanding borrowings $ (146,500)