v2.4.0.6
Trade Accounts Receivable (Details) (USD $)
Dec. 31, 2012
Dec. 31, 2011
Trade Accounts Receivable    
Total trade accounts receivable $ 228,267,000 $ 231,444,000
Allowance for doubtful accounts (16,894,000) (18,484,000)
Total trade accounts receivable, net 211,373,000 212,960,000
Advances and progress billings for contracts in process 5,000,000 12,000,000
Trade accounts receivables
   
Trade Accounts Receivable    
Total trade accounts receivable 188,463,000 203,774,000
Contracts in process
   
Trade Accounts Receivable    
Total trade accounts receivable $ 39,804,000 $ 27,670,000