Loans and Asset Quality Information (Details 10) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Activity in the allowance for loan losses for covered loans
Provisions	$ 11,149	$ 21,555
Loans receivable:
Ending balance - total	263,468	342,100	282,314
Covered
Activity in the allowance for loan losses for covered loans
Beginning balance	4,759	5,808	5,808
Charge-offs	(5,109)	(2,434)	(10,728)
Recoveries
Provisions	5,378	2,998	9,679
Ending balance	5,028	6,372	4,759
Ending balances: Allowance for loan losses
Individually evaluated for impairment	4,656	6,372	4,459
Collectively evaluated for impairment	372		300
Loans acquired with deteriorated credit quality	17	98	17
Loans receivable:
Ending balance - total	263,468	342,100	282,314
Ending balances: Loans
Individually evaluated for impairment	87,661	49,244	74,914
Collectively evaluated for impairment	175,807	292,856	207,400
Loans acquired with deteriorated credit quality	$ 4,726	$ 5,202	$ 4,825

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