Summary of Financial and Nonfinancial Assets Measured at Fair Value on a Nonrecurring Basis (Detail) (Fair Value on a Nonrecurring, USD $)
In Thousands, unless otherwise specified

Dec. 31, 2012

Dec. 31, 2011

Impaired Loans

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Total Fair value

$ 8,192

$ 12,022

OREO

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Total Fair value

5,914

OREO | Not covered by loss share agreements

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Total Fair value

5,704

OREO | Covered by loss share agreements

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Total Fair value

3,255

Goodwill Insurance Agencies

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Total Fair value

9,405

Level 3 | Impaired Loans

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Total Fair value

8,192

12,022

Level 3 | OREO

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Total Fair value

5,914

Level 3 | OREO | Not covered by loss share agreements

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Total Fair value

5,704

Level 3 | OREO | Covered by loss share agreements

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Total Fair value

3,255

Level 3 | Goodwill Insurance Agencies

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Total Fair value

$ 9,405