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Allowance for Probable Loan Losses (Details) (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Allowance for probable loan losses
Balance at the beginning of the period	$ 84,482	$ 95,393
Recoveries credited to allowance	3,820	998
Net losses charged to allowance	(13,909)	(28,038)
Provision (credit) charged to operations	7,833	15,495
Balance at the end of the period	78,406	82,850
Commercial
Allowance for probable loan losses
Balance at the beginning of the period	22,046
Losses charged to allowance	(11,873)
Recoveries credited to allowance	2,982
Net losses charged to allowance	(8,891)
Provision (credit) charged to operations	6,425
Balance at the end of the period	19,580
Commercial real estate: other construction and land development
Allowance for probable loan losses
Balance at the beginning of the period	26,695
Losses charged to allowance	(1,458)
Recoveries credited to allowance	133
Net losses charged to allowance	(1,325)
Provision (credit) charged to operations	(7,088)
Balance at the end of the period	18,282
Commercial real estate: farmland and commercial
Allowance for probable loan losses
Balance at the beginning of the period	16,340
Losses charged to allowance	(1,955)
Recoveries credited to allowance	235
Net losses charged to allowance	(1,720)
Provision (credit) charged to operations	9,324
Balance at the end of the period	23,944
Commercial real estate: multifamily
Allowance for probable loan losses
Balance at the beginning of the period	53
Provision (credit) charged to operations	996
Balance at the end of the period	1,049
Residential: first lien
Allowance for probable loan losses
Balance at the beginning of the period	10,059
Losses charged to allowance	(701)
Recoveries credited to allowance	5
Net losses charged to allowance	(696)
Provision (credit) charged to operations	(3,564)
Balance at the end of the period	5,799
Residential: junior lien
Allowance for probable loan losses
Balance at the beginning of the period	2,611
Losses charged to allowance	(979)
Recoveries credited to allowance	279
Net losses charged to allowance	(700)
Provision (credit) charged to operations	4,215
Balance at the end of the period	6,126
Consumer
Allowance for probable loan losses
Balance at the beginning of the period	6,241
Losses charged to allowance	(750)
Recoveries credited to allowance	181
Net losses charged to allowance	(569)
Provision (credit) charged to operations	(3,554)
Balance at the end of the period	2,118
Foreign
Allowance for probable loan losses
Balance at the beginning of the period	437
Losses charged to allowance	(13)
Recoveries credited to allowance	5
Net losses charged to allowance	(8)
Provision (credit) charged to operations	1,079
Balance at the end of the period	$ 1,508

X

- Definition

Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, net of collections of loans and lease receivables which had previously been fully or partially charged off as bad debts.

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X

- Definition

Reflects an add back to the net allowance balance for loans and lease receivables for recoveries on previously charged off loan receivables.

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X

- Definition

Reflects the gross amount charged against earnings during the period as credit losses (bad debt expense) based on review of the loan and lease portfolio and application of the methodology for estimating credit losses.

+ 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 210.9-03.7(d))

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 20

-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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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X

- Definition

Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities.

+ 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 210.9-03.7(d))

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



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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 20

-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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 9

-Section 03

-Paragraph 7

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5212-111524

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- Definition

The allowance for loan and lease losses represents the reserve to cover probable credit losses related to specifically identified loans and leases, as well as probable credit losses inherent in the remainder of the loan portfolio as of the balance sheet date. For banks, include currently required allocated transfer risk reserves. Include carryover of or adjustments to the allowance for loan losses in connection with business combinations determined to be appropriate.

+ 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 8

-Subparagraph a(ii)

-Subsection I

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.



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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 20

-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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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



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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 8, 9

-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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