Investments in Affordable Housing Limited Partnerships (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Other Assets
Schedule of Equity Method Investments [Line Items]
Investment in affordable housing limited partnerships	$ 18,000,000		$ 18,300,000
Other Liabilities
Schedule of Equity Method Investments [Line Items]
Obligations relating to investments in affordable housing limited partnerships	14,100,000		15,000,000
Other Non-Interest Expense
Schedule of Equity Method Investments [Line Items]
Expense relating to investments in affordable housing limited partnerships	257,000	376,000
Income Tax Expense
Schedule of Equity Method Investments [Line Items]
Affordable housing tax credits and other tax benefits	$ 358,000	$ 551,000