Deposits - Components of interest expense and other information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Banking and Thrift [Abstract]
Money market and other	$ 7,818	$ 7,566	$ 6,322
Savings deposits	2,800	3,364	2,945
Time deposits	12,703	10,424	10,978
Interest on deposits	$ 23,321	$ 21,354	$ 20,245

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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

Interest expense incurred on all money market deposits.

+ References

+ Details

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- Definition

Interest expense incurred on all savings account deposits.

+ References

+ Details

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- Definition

The aggregate interest expense incurred on time deposits, including certificates of deposits, in domestic offices.

+ References

+ Details

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