Loans Receivable and Allowance for Loan Losses (Details 2) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Loans receivable and allowance for loan losses disclosures
30-59 Days Past Due	$ 105,939,000	$ 146,782,000
60-89 Days Past Due	32,184,000	37,637,000
Current	12,082,019,000	12,670,088,000
Impaired loans	386,040,000	346,906,000
Bankruptcy loans | Non-performing
Loans receivable and allowance for loan losses disclosures
Loans which were current or less than 90 days past due	64,300,000
30-59 Days Past Due	5,900,000
60-89 Days Past Due	535,000
Current	57,800,000
Loans discharged prior to 2012 included in loans which are less than 90 days past due	49,900,000
Impaired loans	88,000,000
Loans discharged prior to 2012 included in impaired loans	$ 66,300,000