Fair Value Disclosures (Assets Measured at Fair Value on a Nonrecurring Basis) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans	$ 80,085	$ 65,731
Foreclosed assets	18,349	26,245
Total Impaired loans and Foreclosed assets	98,434	91,976
Quoted Prices In Active Markets For Identical Instruments (Level 1) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans	0	0
Foreclosed assets	0	0
Total Impaired loans and Foreclosed assets	0	0
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans	0	0
Foreclosed assets	0	0
Total Impaired loans and Foreclosed assets	0	0
Significant Unobservable Inputs (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans	80,085	65,731
Foreclosed assets	18,349	26,245
Total Impaired loans and Foreclosed assets	$ 98,434	$ 91,976