Credit Quality of Loans and Allowance for Loan Losses (Troubled Debt Restructurings on Financing Receivables) (Details) (Residential mortgage portfolio [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2013 loan
Residential mortgage portfolio [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Number of Contracts	1
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 246
Financing Receivable, Modifications, Post-Modification Recorded Investment	261
Financing Receivable, Modifications, Recorded Investment	$ 261