Interest Rate Derivative Instruments (Narrative) (Details) (USD $)	3 Months Ended	9 Months Ended		3 Months Ended		9 Months Ended				9 Months Ended
	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014 Interest Rate Swap [Member]	Sep. 30, 2013 Interest Rate Swap [Member]	Sep. 30, 2014 Interest Rate Swap [Member]	Sep. 30, 2013 Interest Rate Swap [Member]	Sep. 30, 2014 Interest Rate Swap [Member] Fair Value Measurements, Level 2 [Member]	Dec. 31, 2013 Interest Rate Swap [Member] Fair Value Measurements, Level 2 [Member]	Sep. 30, 2014 Cash Flow Hedging [Member] Interest Rate Swap [Member]	Feb. 29, 2012 Cash Flow Hedging [Member] Interest Rate Swap [Member]	Feb. 08, 2012 Cash Flow Hedging [Member] Interest Rate Swap [Member]
Derivative [Line Items]
Derivative inception date										Feb. 08, 2012
Derivative instruments, notional amount											$ 150,000,000	$ 150,000,000
Derivative maturity date										Sep. 28, 2014
Unrealized gains or losses on cash flow hedge derivative effective portion		0	200,000
Interest expense related to payments on interest rate swaps	5,410,000	9,683,000		200,000	100,000	500,000	400,000
Interest rate swap liability recorded at fair value								$ 0	$ 500,000