Derivatives and Hedging Activities (Details) (Not Designated as Hedging Instrument [Member], Interest Rate Contracts [Member], USD $)	Mar. 31, 2012	Mar. 31, 2011
Derivative [Line Items]
Notional Amount of Interest Rate Derivative Instruments Not Designated as Hedging Instruments	$ 171,300,000	$ 160,300,000
Other Assets [Member]
Derivative [Line Items]
Fair value of asset derivative instruments	14,950,000	9,050,000
Other Liabilities [Member]
Derivative [Line Items]
Fair value of liability derivative instruments	$ 14,950,000	$ 9,050,000