Debt with Commercial Bank (Narrative) (Details) (USD $)	3 Months Ended				0 Months Ended	3 Months Ended		0 Months Ended	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Apr. 26, 2012 Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Apr. 26, 2012 Secured Syndicated Credit Facility [Member] Revolving Credit Facility [Member] Citi Bank [Member]	Mar. 31, 2013 Secured Syndicated Credit Facility [Member] Revolving Credit Facility [Member] Citi Bank [Member]	Apr. 26, 2012 Credit Agreement, Seventh Amendment [Member] BOA [Member]	Apr. 26, 2012 Secured Term Loan [Member] Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Mar. 31, 2013 Secured Term Loan [Member] Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Mar. 31, 2013 Minimum [Member] Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Mar. 31, 2013 Mid-range [Member] Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Mar. 31, 2013 Maximum [Member] Secured Syndicated Credit Facility [Member] Citi Bank [Member]
Line of Credit Facility [Line Items]
Debt instrument, face amount				$ 100,000,000			$ 55,000,000	$ 45,000,000
Line of credit facility, term					4 years
Credit agreement, maximum borrowing capacity					45,000,000
Credit agreement, amortization period								4 years
Line of Credit Facility, Expansion					10,000,000
Description of variable interest rate basis			LIBOR
Basis spread on variable interest rate										1.50%	1.70%	2.00%
Deferred Costs, Credit Card Origination Costs, Amount			574,000	744,000
Credit agreement, amount outstanding						37,800,000
Line of credit, interest rate at period end						1.70%
Credit agreement, average amount outstanding during period						37,800,000
Credit agreement, maximum amount outstanding during period						37,800,000
Long-term Debt									36,800,000
Credit agreement, current amount outstanding									9,600,000
Current maturities, period									12 months
Effective interest rate									1.70%
Repayments of term loan	12,000	0							4,100,000
Long-term Debt, Excluding Current Maturities									$ 27,200,000