Scheduled Maturities of CDs (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Deposits From Banking Clients [Line Items]
1 year or less	$ 5,471,551
More than 1 year through 2 years	1,166,187
More than 2 years through 3 years	318,106
More than 3 years through 4 years	124,296
More than 4 years through 5 years	284,625
Over 5 years	8,498
Total CDs	$ 7,373,263	$ 7,835,161

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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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

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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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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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