Assets Measured at Fair Value on a Non-Recurring Basis (Detail) (USD $) In Thousands	Jun. 30, 2011		Dec. 31, 2010
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale			$ 3,233
Certain impaired loans	104,444		237,975
Other assets	16,618	[1]
Assets, Fair Value Disclosure, Total	121,062		241,208
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale			3,233
Other assets	16,618	[1]
Assets, Fair Value Disclosure, Total	16,618		3,233
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Certain impaired loans	104,444		237,975
Assets, Fair Value Disclosure, Total	$ 104,444		$ 237,975

[1] Represents the fair value of OREO that was measured at fair value subsequent to its initial classification as OREO.