Time Certificates of Deposit (Schedule of Time Certifcates of Deposit Maturities) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Deposits [Abstract]
Time deposits amounts scheduled to mature April 1, 2013 through December 31, 2013	$ 430,608
Time deposits weighted average rate for maturities April 1, 2013 to December 31, 2013	0.78%
Time deposits amounts scheduled to mature in 2014	190,671
Time deposits weighted average rate for maturities in 2014	1.49%
Time deposits amounts scheduled to mature in 2015	117,668
Time deposits weighted average rate for maturities in 2015	2.14%
Time deposits amounts scheduled to mature in 2016	73,416
Time deposits weighted average rate for maturities in 2016	1.74%
Time deposits amounts scheduled to mature in 2017	40,197
Time deposits weighted average rate for maturities in 2017	1.58%
Time deposits amounts schedule to mature in 2018 and after	9,392
Time deposits weighted average rate for maturities in 2018 and after	1.26%
Time deposits	$ 861,952	$ 870,232

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Amount of time deposits maturing after the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 45

-Subparagraph a

-IssueDate 2006-05-01

-Chapter 13

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of time deposits maturing in the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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Amount of time deposits maturing in the fourth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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Amount of time deposits maturing in the next fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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Amount of time deposits maturing in the third fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

+ References

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Amount of time deposits maturing in the second fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

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Weighted average interest rate for time deposits held by the entity with maturities greater than five years.

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Weighted average interest rate for time deposits held by the entity with maturities greater than four years, but five years or less.

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Weighted average interest rate for time deposits held by the entity with maturities greater than three years, but four years or less.

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Weighted average interest rate for time deposits held by the entity with maturities of one year or less.

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Weighted average interest rate for time deposits held by the entity with maturities greater than two years, but three years or less.

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Weighted average interest rate for time deposits held by the entity with maturities greater than one year, but two years or less.

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