Derivative Financial Instruments (Narrative) (Details) (USD $)				0 Months Ended	12 Months Ended		0 Months Ended	12 Months Ended	0 Months Ended		0 Months Ended			0 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012	Oct. 04, 2011 Union Bank [Member]	Dec. 31, 2013 Union Bank [Member]	Dec. 31, 2012 Union Bank [Member]	Oct. 04, 2011 Bank Of America [Member]	Dec. 31, 2013 Bank Of America [Member]	Feb. 06, 2009 Interest Rate Swap [Member] Credit Facility [Member]	Mar. 03, 2008 Interest Rate Swap [Member] Loans [Member]	Aug. 09, 2013 Swap [Member]	Dec. 31, 2013 Swap [Member]	Sep. 30, 2013 Swap [Member]	Oct. 04, 2011 Interest Rate Swap [Member] Union Bank [Member]	Oct. 04, 2011 Interest Rate Swap [Member] Bank Of America [Member]	Aug. 09, 2013 LIBOR [Member] Swap [Member]
Derivative Financial Instruments [Line Items]
Term of swap agreement											3 years
Basis spread on variable rate																1.20%
Notional amount	$ 149,000,000	$ 149,000,000
Swap agreement collateral												40,000,000	40,000,000
Secured loan	20,000,000		20,000,000						120,000,000	18,000,000
Fixed rate									1.93%	4.25%
Maturity date of senior notes									January 3, 2012
Loan maximum borrowing capacity	$ 200,000,000					$ 20,000,000	$ 18,000,000	$ 20,000,000
Floating rate, LIBOR plus basis points (as a percentage)					0.40%			0.40%						0.40%	0.50%
Loan mature date				Jan. 02, 2015			Mar. 01, 2013