Fair Value Fair Value (Impaired Financing Receivables Additional Information) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Schedule of Impaired Financing Receivables Additional Information [Line Items]
Book Value Of Impaired Loans Carried At Fair Value	$ 15,841	$ 19,643
Partial Charge-Offs On Impaired Loans carried at Fair Value	11,837	19,731
Impaired Financing Receivable, Related Allowance	5,738	3,660
impaired Financing Receivable, loans not held at Fair Value, Carrying Amount	50,887	53,089
Impaired Financing Receivable, Recorded Investment	69,224	73,712	$ 76,231
Impaired loans carried at fair value	12,599	16,963
Impaired Financing Receivable, loans not held at Fair Value, Recorded Investment	53,383	54,069
Partial Charge-offs on Impaired Loans carried at Cost	18,147	12,749
Impaired Financing Receivable, Carrying Value	63,486	70,052
Partial Charge-Offs On Impaired Loans	29,984	32,480
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	5,738	3,660
Financing Receivable, not collateral dependent [Domain]
Schedule of Impaired Financing Receivables Additional Information [Line Items]
Impaired Financing Receivable, Related Allowance	2,496	980
Commercial Receivables, excluding Commercial, Financial, and Agricultural [Domain]
Schedule of Impaired Financing Receivables Additional Information [Line Items]
Impaired Financing Receivable, Related Allowance	$ 3,242	$ 2,680