Deposits (Details 1) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Maturing by:
June 30, 2012	$ 3,015,421		$ 3,015,421
June 30, 2013	599,159		599,159
June 30, 2014	21,121		21,121
June 30, 2015	47,349		47,349
June 30, 2016	38,262		38,262
Total	3,721,312		3,721,312		3,690,305
Interest expense on deposits
Savings and money market	2,095	2,179	4,039	4,444
Certificates of deposit	11,364	13,164	22,859	27,310
Fees for early withdrawal	(61)	(64)	(117)	(117)
Total interest expense on deposits	$ 13,398	$ 15,279	$ 26,781	$ 31,637

Maturing by.

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Amount of interest-bearing domestic certificate of deposit liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 12
-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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Aggregate amount of interest expense on all deposits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher OTS
-Name Federal Regulation (FR)
-Number Title 12
-Chapter V
-Section 563c.102
-Paragraph 6
-Subsection II
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 6
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Reference 3: 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

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Amount of interest expense on domestic certificates of deposit liabilities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 6
-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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- Definition

Early withdrawal penalties on domestic deposits which discourage customer withdrawal prior to maturity.

+ References

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The aggregate interest expense incurred on the following for deposits in domestic offices: (1) transaction accounts (NOW, and telephone and preauthorized transfer accounts), (2) money market deposits and (3) savings deposits.

+ References

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- Definition

Amount of time deposits (including certificates of deposits, individual retirement accounts and open accounts) held by the entity with a remaining term of greater than four years but five years or less.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Audit and Accounting Guide (AAG)
-Number AAG-DEP
-Chapter 13
-Paragraph 45
-Subparagraph a
-IssueDate 2006-05-01
-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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-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
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Amount of time deposits (including certificates of deposits, individual retirement accounts and open accounts) held by the entity with a remaining term of greater than three years but four years or less.

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Amount of time deposits (including certificates of deposits, individual retirement accounts and open accounts) held by the entity with a remaining term of twelve months or less.

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Amount of time deposits (including certificates of deposits, individual retirement accounts and open accounts) held by the entity with a remaining term of greater than two years but three years or less.

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Amount of time deposits (including certificates of deposits, individual retirement accounts and open accounts) held by the entity with a remaining term of greater than twelve months, but two years or less.

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