Long-Term Debt (Interest Rate Swaps) (Details) (Interest Rate Swap [Member], USD $)				3 Months Ended
	Dec. 31, 2012	Mar. 31, 2013 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 2 [Member]	Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 2 [Member]	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012 September 2013 [Member]	Dec. 31, 2012 October 2013 Thru September 2014 [Member]	Dec. 31, 2012 October 2014 [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 200,000,000
Fixed Interest Rate of Swap	1.73%
Quarterly Amortization of Interest Rate Swap Notional Amount						2,500,000	5,000,000	7,500,000
Remaining Balance Of Interest Rate Swap Notional Amount	107,500,000
Derivative Assets		5,593,000
Derivative Financial Instruments, Liabilities, Fair Value Disclosure			(6,486,000)
Interest Rate Swap Unrealized Gain Loss				554,000	(75,000)
Deferred Taxes Pertaining To Other Comprehensive Income Relating to Swaps				$ (300,000)	$ 100,000