Receivables Narrative (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Doubtful Accounts Receivable	$ 22,213,000	$ 24,767,000
Number of Missed Payments before Delinquent	3
Typical Financing Period	12 months
Credit amount requiring additional analysis	250,000
Average Period of Adjudication	18 months
Installment receivable purchased from DLL	$ 2,609,000	$ 3,806,000