Loans and Servicing (Details 4) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2013	Dec. 31, 2012
Recorded Investment
Impaired loans without a valuation allowance	$ 429	$ 32
Impaired loans with a valuation allowance	2,730	3,083
Unpaid Principal Balance
Impaired loans without a valuation allowance	429	32
Impaired loans with a valuation allowance	2,833	3,216
Related Allowance
Impaired loans with a valuation allowance	217	320
Average Recorded Investment
Impaired loans without a valuation allowance	390	1,351
Impaired loans with a valuation allowance	2,818	1,711
Interest Income Recognized
Impaired loans without a valuation allowance	1	23
Impaired loans with a valuation allowance	102	30
One- to four- family, residential loans
Recorded Investment
Impaired loans with a valuation allowance	322	658
Unpaid Principal Balance
Impaired loans with a valuation allowance	322	684
Related Allowance
Impaired loans with a valuation allowance	7	93
Average Recorded Investment
Impaired loans without a valuation allowance		176
Impaired loans with a valuation allowance	397	734
Interest Income Recognized
Impaired loans with a valuation allowance	9	10
Home equity loans and lines of credit
Recorded Investment
Impaired loans without a valuation allowance	429	32
Impaired loans with a valuation allowance		13
Unpaid Principal Balance
Impaired loans without a valuation allowance	429	32
Impaired loans with a valuation allowance		13
Related Allowance
Impaired loans with a valuation allowance		13
Average Recorded Investment
Impaired loans without a valuation allowance	390	30
Impaired loans with a valuation allowance	11	13
Interest Income Recognized
Impaired loans without a valuation allowance	1
Impaired loans with a valuation allowance		1
Commercial real estate
Recorded Investment
Impaired loans with a valuation allowance	2,408	2,412
Unpaid Principal Balance
Impaired loans with a valuation allowance	2,511	2,519
Related Allowance
Impaired loans with a valuation allowance	210	214
Average Recorded Investment
Impaired loans with a valuation allowance	2,410	958
Interest Income Recognized
Impaired loans with a valuation allowance	93	19
Commercial business
Average Recorded Investment
Impaired loans with a valuation allowance		6
One-to-four family, construction loans
Average Recorded Investment
Impaired loans without a valuation allowance		801
Multi-family
Average Recorded Investment
Impaired loans without a valuation allowance		344
Interest Income Recognized
Impaired loans without a valuation allowance		$ 23

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