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Allowance for Probable Loan Losses (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Allowance for probable loan losses |  |  |
Balance at the beginning of the period | $ 84,482 | $ 95,393 | $ 73,461
Losses charged to allowance | (22,899) | (35,240) | (38,539)
Recoveries credited to allowance | 5,291 | 1,517 | 1,638
Net losses charged to allowance | (17,608) | (33,723) | (36,901)
Provision (credit) charged to operations | 17,318 | 22,812 | 58,833
Balance at the end of the period | 84,192 | 84,482 | 95,393
Commercial |  |  |
Allowance for probable loan losses |  |  |
Balance at the beginning of the period | 22,046 |  |
Losses charged to allowance | (16,130) |  |
Recoveries credited to allowance | 4,126 |  |
Net losses charged to allowance | (12,004) |  |
Provision (credit) charged to operations | 16,575 |  |
Balance at the end of the period | 26,617 |  |
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 | (1,467) |  |
Recoveries credited to allowance | 171 |  |
Net losses charged to allowance | (1,296) |  |
Provision (credit) charged to operations | (5,459) |  |
Balance at the end of the period | 19,940 |  |
Risks related to family development loans |  |  |
Minimum number of family development loans | 1 |  |
Maximum number of family development loans | 4 |  |
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 | 296 |  |
Net losses charged to allowance | (1,659) |  |
Provision (credit) charged to operations | 9,546 |  |
Balance at the end of the period | 24,227 |  |
Commercial real estate: multifamily |  |  |
Allowance for probable loan losses |  |  |
Balance at the beginning of the period | 53 |  |
Provision (credit) charged to operations | 950 |  |
Balance at the end of the period | 1,003 |  |
Residential: first lien |  |  |
Allowance for probable loan losses |  |  |
Balance at the beginning of the period | 10,059 |  |
Losses charged to allowance | (805) |  |
Recoveries credited to allowance | 28 |  |
Net losses charged to allowance | (777) |  |
Provision (credit) charged to operations | (4,720) |  |
Balance at the end of the period | 4,562 |  |
Residential: junior lien |  |  |
Allowance for probable loan losses |  |  |
Balance at the beginning of the period | 2,611 |  |
Losses charged to allowance | (1,304) |  |
Recoveries credited to allowance | 300 |  |
Net losses charged to allowance | (1,004) |  |
Provision (credit) charged to operations | 3,153 |  |
Balance at the end of the period | 4,760 |  |
Consumer |  |  |
Allowance for probable loan losses |  |  |
Balance at the beginning of the period | 6,241 |  |
Losses charged to allowance | (1,067) |  |
Recoveries credited to allowance | 211 |  |
Net losses charged to allowance | (856) |  |
Provision (credit) charged to operations | (3,661) |  |
Balance at the end of the period | 1,724 |  |
Foreign |  |  |
Allowance for probable loan losses |  |  |
Balance at the beginning of the period | 437 |  |
Losses charged to allowance | (171) |  |
Recoveries credited to allowance | 159 |  |
Net losses charged to allowance | (12) |  |
Provision (credit) charged to operations | 934 |  |
Balance at the end of the period | $ 1,359 |  |

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- 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. + References No definition available. + Details
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- Definition Reflects an add back to the net allowance balance for loans and lease receivables for recoveries on previously charged off loan receivables. + References No definition available. + Details
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- Definition Reflects the maximum number of family development loans that include restrictive underwriting standards that inhibit the buys from obtaining long term financing and excessive housing and lot inventory in the market. + References No definition available. + Details
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- Definition Reflects the minimum number of family development loans that include restrictive underwriting standards that inhibit the buys from obtaining long term financing and excessive housing and lot inventory in the market. + References No definition available. + Details
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- 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)) -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 -Subparagraph d 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 + Details
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- 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 -Subparagraph d 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 + Details
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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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 9 -Section 03 -Paragraph 7 -Subparagraph d Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 5 -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. Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 + Details
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