Fair Value Measurement and Fair Value of Financial Instruments (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	$ 1,288	$ 5,435	$ 6,900
Impaired Financing Receivable, Related Allowance	219	645	758
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	1,275	1,500
Available-for-sale Securities, Gross Unrealized Gain (Loss), Total	8,236	16,316
Collateralized mortgage obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Gross Unrealized Gain (Loss), Total	$ 24	$ 0