Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation (Details 3)

v2.4.0.6
Basis of Presentation (Details 3) (USD $)
In Thousands, unless otherwise specified
Jun. 30, 2012
Dec. 31, 2011
Summary of investment categories    
Restricted cash and investments, cost $ 2,841 $ 11,341
Restricted cash and investments, gross unrealized gains      
Restricted cash and investments, gross unrealized losses      
Restricted cash and investments, estimated fair value 2,841 11,341
Certificates of deposit [Member]
   
Summary of investment categories    
Restricted cash and investments, cost 1,500 10,000
Restricted cash and investments, gross unrealized gains      
Restricted cash and investments, gross unrealized losses      
Restricted cash and investments, estimated fair value 1,500 10,000
Certificates of deposit - restricted [Member]
   
Summary of investment categories    
Restricted cash and investments, cost 1,341 1,341
Restricted cash and investments, gross unrealized gains      
Restricted cash and investments, gross unrealized losses      
Restricted cash and investments, estimated fair value $ 1,341 $ 1,341