Portfolio Loans Covered by Loss Share (Covered loans) - Allowance for Credit Losses on Financing Receivables (Details) (USD $) In Thousands, unless otherwise specified			3 Months Ended		9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Covered Loans	Sep. 30, 2011 Covered Loans	Sep. 30, 2012 Covered Loans	Sep. 30, 2011 Covered Loans
Summary of Activity in the Allowance for Loan Losses for Covered Loans [Roll Forward]
Balance at beginning of period	$ 11,102	$ 1,635	$ 1,889	$ 0	$ 1,635	$ 0
Provision charged to expense			10,889	2,672	13,380	2,947
Loans charged off			(1,627)	(103)	(3,689)	(378)
Recoveries			10	0	16	0
Other			(59)	0	(240)	0
Balance at beginning of period	$ 11,102	$ 1,635	$ 11,102	$ 2,569	$ 11,102	$ 2,569