Deposits and Borrowed Funds (Details 4) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Maturity distribution of long-term debt
2016	$ 16,100,000
2017	40,600,000
2018	25,100,000
2019	92,200,000
Thereafter	464,600,000
Total long-term debt	638,600,000us-gaap_LongTermDebt	735,968,000us-gaap_LongTermDebt
Remaining borrowing capacity secured by collateral with FHLB	6,010,000,000
Senior notes
Maturity distribution of long-term debt
Thereafter	299,500,000
Total long-term debt	299,500,000
Subordinated and junior subordinated debt
Maturity distribution of long-term debt
2019	75,000,000
Thereafter	155,200,000
Total long-term debt	230,200,000
Nonrecourse debt
Maturity distribution of long-term debt
2016	16,100,000
2017	30,800,000
2018	25,100,000
2019	17,200,000
Thereafter	9,900,000
Total long-term debt	99,100,000
Other long-term debt
Maturity distribution of long-term debt
2017	9,800,000
Total long-term debt	$ 9,800,000

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