Acquisitions (Narrative) (Details) (USD $)	Dec. 31, 2012	Sep. 30, 2012	Oct. 31, 2012 South Valley Bank [Member] branches	Oct. 31, 2012 Received from South Valley [Member] South Valley Bank [Member]
Business Acquisition [Line Items]
Loans receivable, net			$ 343,510,000	$ 383,170,000
Covered loans receivable, net			107,075,000	107,075,000
Customer accounts			735,415,000	735,415,000
Transaction deposits acquired	3,571,987,000	2,946,453,000	533,000,000
Number of branches acquired (in branches)			24
Total considerartion			43,895,000
Equity Issued			33,492,000
Cash paid			10,403,000
Potential reduction in purchase price, earn-out assets			$ 14,000,000