Derivative Instruments And Hedging Activities , Derivative Contracts (Details) (USD $) In Millions, unless otherwise specified			3 Months Ended		3 Months Ended
	Mar. 31, 2013 Interest Rate Contract [Member] Derivative_Contracts	Mar. 31, 2013 Interest Rate Swap [Member] Derivative_Contracts	Mar. 31, 2013 Interest Rate Swap [Member] Derivative Maturing 2014 [Member]	Mar. 31, 2013 Interest Rate Cap [Member] Derivative_Contracts	Mar. 31, 2013 Interest Rate Cap [Member] Derivative Maturing 2015 [Member]	Mar. 31, 2013 Interest Rate Cap [Member] Derivative Maturing 2016 [Member]	Mar. 31, 2013 Other Assets [Member]	Dec. 31, 2012 Other Assets [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Collateral Already Posted, Aggregate Fair Value							$ 1.2	$ 1.2
Number of Interest Rate Derivatives Held (number of derivative contracts)	3	1		2
Notional Amount of Derivatives		$ 20.0	$ 20.0	$ 162.4	$ 152.4	$ 10.0
Derivative, Type			Swap		Cap	Cap
Derivative, Purpose			Floating to Fixed Rate		Cap Floating Rate	Cap Floating Rate
Derivative, Effective Date			Jan. 01, 2009		Apr. 01, 2012	Oct. 03, 2011
Derivative, Maturity Date			Jan. 01, 2014		Apr. 01, 2015	Oct. 03, 2016
Derivative, Based on			3 Month LIBOR		3 Month LIBOR	3 Month LIBOR
Derivative, Variable Rate			0.308%		0.306%	0.306%
Derivative, Fixed Rate			2.145%		11.265%	11.02%
Derivative, Spread on Variable Rate			1.87%		0.00%	0.00%
Derivative, Effective Fixed Rate			4.015%