SHORT-TERM BORROWINGS (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Short-term Debt [Line Items]
Short-term borrowings	$ 568,505	$ 615,222
Master Notes [Member]
Short-term Debt [Line Items]
Short-term borrowings	399,047	375,396
Repurchase Agreements [Member]
Short-term Debt [Line Items]
Short-term borrowings	111,907	172,275
Federal Home Loan Bank Advances [Member]
Short-term Debt [Line Items]
Short-term borrowings	55,000	65,000
Federal Funds Purchased [Member]
Short-term Debt [Line Items]
Short-term borrowings	2,551	2,551
Unsecured Debt [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	475,000
Secured Debt [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	$ 1,089,122