Covered Loans 30 to 89 Days, 90 Days or More Past Due (Detail) (Covered Loans, USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 90 days or more past due	$ 347,442	$ 360,827
Loans 30-89 Days Past Due	111,989	130,542
One to Four Family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 90 days or more past due	314,821	310,929
Loans 30-89 Days Past Due	103,495	108,691
Other loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 90 days or more past due	32,621	49,898
Loans 30-89 Days Past Due	$ 8,494	$ 21,851