Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans transferred to property acquired through foreclosure or repossession	$ 3,255	$ 1,251
Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans	5,821	6,599
Loan servicing rights	902	482
Property acquired through foreclosure or repossession	1,139	892
Total sssets at fair value on a nonrecurring basis	7,862	7,973
Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans	0	0
Loan servicing rights	0	0
Property acquired through foreclosure or repossession	0	0
Total sssets at fair value on a nonrecurring basis	0	0
Nonrecurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans	0	0
Loan servicing rights	0	0
Property acquired through foreclosure or repossession	0	0
Total sssets at fair value on a nonrecurring basis	0	0
Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans	5,821	6,599
Loan servicing rights	902	482
Property acquired through foreclosure or repossession	1,139	892
Total sssets at fair value on a nonrecurring basis	7,862	7,973
Allowance For Loan Loss Allocation on Collateral Dependent Impaired Loans	1,000	489
Loans transferred to property acquired through foreclosure or repossession	$ 3,255	$ 1,300