Notes Payable and Long-Term Debt (Schedule of Long-Term Debt) (Details) (USD $)	0 Months Ended			3 Months Ended			3 Months Ended	12 Months Ended	0 Months Ended	3 Months Ended	12 Months Ended	0 Months Ended	3 Months Ended	12 Months Ended		3 Months Ended	12 Months Ended
	Mar. 19, 2009	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2013 Unsecured Debt [Member]	Mar. 31, 2013 Notes Payable, Other Payables [Member]	Dec. 31, 2012 Notes Payable, Other Payables [Member]	Mar. 31, 2013 Promissory Note [Member] Unsecured Debt [Member]	Dec. 31, 2012 Promissory Note [Member] Unsecured Debt [Member]	Dec. 15, 2005 Trust Preferred Security Offering, 2005 [Member] Unsecured Debt [Member]	Mar. 31, 2013 Trust Preferred Security Offering, 2005 [Member] Unsecured Debt [Member]	Dec. 31, 2012 Trust Preferred Security Offering, 2005 [Member] Unsecured Debt [Member]	Jun. 21, 2007 Trust Preferred Security Offering, 2007 [Member] Unsecured Debt [Member]	Mar. 31, 2013 Trust Preferred Security Offering, 2007 [Member] Unsecured Debt [Member]	Dec. 31, 2012 Trust Preferred Security Offering, 2007 [Member] Unsecured Debt [Member]	Dec. 15, 2005 Trust Preferred Security Offering, 2007 [Member] Unsecured Debt [Member]	Mar. 31, 2013 Line of Credit [Member] Secured Debt [Member]	Dec. 31, 2012 Line of Credit [Member] Secured Debt [Member]
Debt Instrument [Line Items]
Long-term debt		$ 25,639,000	$ 25,339,000				$ 9,333,000	$ 9,333,000		$ 9,279,000	$ 9,279,000		$ 3,093,000	$ 3,093,000		$ 3,934,000	$ 3,634,000
Percentage bearing variable interest, percentage rate																4.50%	4.50%
Fixed interest rate									8.83%
Description of variable rate basis	three-month LIBOR			prime				prime	3-month LIBOR			3-month LIBOR				prime	prime
Basis spread on variable rate	3.40%			1.00%				1.00%	3.75%						3.40%
Payment terms							Annual installment payments.	Annual installment payments.		Interest payments due quarterly.	Interest payments due quarterly.		Interest payments due quarterly.	Interest payments due quarterly.		Interest payments due monthly.	Interest payments due monthly.
Line of Credit Facility, Amount Outstanding					$ 10,500,000	$ 10,500,000