Commitments and Contingencies (Schedule of Guarantor Obligations) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
Guarantor Obligations [Line Items]
Guarantor Obligations, Short-Term	$ 142,300,000
Guarantor Obligations, Current Carrying Value	271,095,000	241,482,000	251,717,000
Standby Letters of Credit
Guarantor Obligations [Line Items]
Guarantor Obligations, Current Carrying Value	227,835,000	196,400,000	200,835,000
Loans Sold with Recourse
Guarantor Obligations [Line Items]
Guarantor Obligations, Current Carrying Value	$ 43,260,000	$ 45,082,000	$ 50,882,000