(Interest expense deposits) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Banking and Thrift [Abstract]
NOW accounts	$ 1,011	$ 645	$ 797
Money market accounts	896	386	452
Savings accounts	252us-gaap_InterestExpenseSavingsDeposits	164us-gaap_InterestExpenseSavingsDeposits	204us-gaap_InterestExpenseSavingsDeposits
Certificate of deposit accounts	2,991	2,478	3,016
Interest expense	$ 5,150us-gaap_InterestExpenseDeposits	$ 3,673us-gaap_InterestExpenseDeposits	$ 4,469us-gaap_InterestExpenseDeposits

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Aggregate amount of interest expense on all 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

+ Details

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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

+ 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.

+ References

+ Details

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- Definition

Interest expense incurred on all savings account deposits.

+ References

+ Details

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