Derivative Financial Instruments (Narrative) (Details) (USD $)	0 Months Ended			0 Months Ended
	Oct. 04, 2011 Union Bank [Member]	Dec. 31, 2012 Union Bank [Member]	Dec. 31, 2011 Union Bank [Member]	Oct. 04, 2011 Bank Of America [Member]	Feb. 06, 2009 Interest Rate Swap [Member] Credit Facility [Member]	Dec. 31, 2012 Interest Rate Swap [Member] Loans [Member]	Dec. 31, 2011 Interest Rate Swap [Member] Loans [Member]	Mar. 03, 2008 Interest Rate Swap [Member] Loans [Member]
Derivative Financial Instruments [Line Items]
Secured notes					$ 120,000,000			$ 18,000,000
Fixed rate					1.93%			4.25%
Maturity date of senior notes					January 3, 2012
Loan maximum borrowing capacity		20,000,000	20,000,000	18,000,000
Floating rate, LIBOR plus basis points (as a percentage)	0.40%			0.50%
Loan mature date	Jan. 02, 2015			Mar. 01, 2013
Fair market value of the interest rate swap						$ 103,000	$ 670,000