Deposits (Schedule Of Maturities For Time Deposits) (Details) (USD $)	Dec. 31, 2011
Time Deposits [Line Items]
2012	$ 3,891,643,000
2013	261,987,000
2014	176,277,000
2015	191,000
2016	1,228,000
Thereafter
Time Deposits	4,331,326,000
Time Deposits, $100,000 And Over [Member]
Time Deposits [Line Items]
2012	3,106,609,000
2013	228,188,000
2014	162,437,000
2016	1,095,000
Thereafter
Time Deposits	3,498,329,000
Other Time Deposits [Member]
Time Deposits [Line Items]
2012	785,034,000
2013	33,799,000
2014	13,840,000
2015	191,000
2016	133,000
Thereafter
Time Deposits	$ 832,997,000

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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 five years.

+ 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: 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

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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 four years but five years or less.

+ References

+ Details

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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.

+ References

+ Details

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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.

+ References

+ Details

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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.

+ References

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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.

+ References

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The aggregate amount of time deposits, including certificates of deposits, individual retirement accounts and open accounts.

+ 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

-Subparagraph (SX 210.9-03.12)

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

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