Deposits - Components of interest expense recognized on interest-bearing deposits (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Interest expense recognized on interest-bearing deposits
Savings	$ 32	$ 47	$ 52
Money market	392	692	1,035
NOW accounts	270	321	447
Time certificates of deposit	936	1,602	2,179
Total interest expense recognized	$ 1,630	$ 2,662	$ 3,713

Aggregate amount of all interest expense on domestic deposit liabilities.

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- Definition

Amount of interest expense on domestic certificates of deposit liabilities.

+ References

+ Details

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- Definition

Interest expense incurred on all money market deposits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.6)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 6

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Section 563c.102

-Paragraph 6

-Chapter V

-Subsection II

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

+ Details

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- Definition

Interest expense incurred on the amount of Negotiable Order of Withdrawal (NOW). Interest-bearing transaction account that combines the payable on demand feature of checks and investment feature of savings accounts. A NOW account is functionally an interest paying checking account.

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+ Details

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- Definition

Interest expense incurred on all savings account deposits.

+ References

+ Details

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