Deposits and Borrowed Funds (Details 4) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Maturity distribution of long-term debt
2014	$ 11,200,000
2015	22,400,000
2016	21,900,000
2017	13,200,000
Thereafter	637,400,000
Total long-term debt	706,051,000	697,778,000
Remaining borrowing capacity secured by collateral with FHLB	4,520,000,000
Subordinated and junior subordinated debt
Maturity distribution of long-term debt
Thereafter	333,400,000
Total long-term debt	333,400,000
Nonrecourse debt
Maturity distribution of long-term debt
2014	11,200,000
2015	22,400,000
2016	21,900,000
2017	13,200,000
Thereafter	6,400,000
Total long-term debt	75,104,000
Senior notes
Maturity distribution of long-term debt
Thereafter	297,600,000
Total long-term debt	$ 297,600,000