v2.4.0.6
Fair Value Measurements (Details) (USD $)
12 Months Ended
Dec. 31, 2011
Mar. 31, 2012
Extinguishment of Debt [Line Items]    
Carrying value of outstanding debt $ 207,163,000 $ 207,253,000
Number of completed acquisitions 2  
Long-Term Debt [Member]
   
Extinguishment of Debt [Line Items]    
Fair value of outstanding debt   237,333,000
Carrying value of outstanding debt   $ 207,253,000
Senior Subordinated Notes, interest rate   8.00%