Debt with Commerical Bank (Details) (USD $)	9 Months Ended					9 Months Ended		0 Months Ended	9 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 Secured Syndicated Credit Facility [Member]	Sep. 30, 2012 Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Apr. 26, 2012 Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Sep. 30, 2012 Secured Syndicated Credit Facility [Member] Revolving Credit Facility [Member] Citi Bank [Member] Y	Apr. 26, 2012 Secured Syndicated Credit Facility [Member] Revolving Credit Facility [Member] Citi Bank [Member]	Apr. 26, 2012 Credit Agreement, Seventh Amendment [Member] BOA [Member]	Sep. 30, 2012 Secured Term Loan [Member] Secured Syndicated Credit Facility [Member] Citi Bank [Member] Y	Apr. 26, 2012 Secured Term Loan [Member] Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Sep. 30, 2012 Secured Term Loan [Member] Credit Agreement, Seventh Amendment [Member] BOA [Member]	Sep. 30, 2012 Minimum [Member] Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Sep. 30, 2012 Mid-range [Member] Secured Syndicated Credit Facility [Member] Citi Bank [Member]	Sep. 30, 2012 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
Credit agreement, maximum borrowing capacity							45,000,000
Credit agreement, amortization period									4
Line of Credit Facility, Expansion							10,000,000
Description of variable interest rate basis				LIBOR
Basis spread on variable interest rate												1.50%	1.74%	2.00%
Repayments of term loan	600,000	0						45,140,000	2,100,000		1,700,000
Document Period End Date	Sep. 30, 2012		Sep. 30, 2012
Credit agreement, amount outstanding						37,800,000
Line of credit, interest rate at period end						1.74%
Credit agreement, average amount outstanding during period						30,600,000
Credit agreement, maximum amount outstanding during period						37,800,000
Long-term Debt									42,900,000
Credit agreement, current amount outstanding									$ 11,000,000
Current maturities, period									12 months
Effective interest rate									1.74%