Fair Value Fair Value (Impaired Financing Receivables Additional Information) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Schedule of Impaired Financing Receivables Additional Information [Line Items]
Book Value Of Impaired Loans Carried At Fair Value	$ 12,520	$ 19,643
Partial Charge-Offs On Impaired Loans carried at Fair Value	13,228	19,731
Impaired Financing Receivable, Related Allowance	5,064	3,660
impaired Financing Receivable, loans not held at Fair Value, Carrying Amount	56,133	53,089
Impaired Financing Receivable, Recorded Investment	70,492	73,712	105,873
Impaired loans carried at fair value	9,295	16,963
Impaired Financing Receivable, loans not held at Fair Value, Recorded Investment	57,972	54,069
Partial Charge-offs on Impaired Loans carried at Cost	12,564	12,749
Impaired Financing Receivable, Carrying Value	65,428	70,052
Partial Charge-Offs On Impaired Loans	25,792	32,480
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	5,064	3,660
Financing Receivable, not collateral dependent [Domain]
Schedule of Impaired Financing Receivables Additional Information [Line Items]
Impaired Financing Receivable, Related Allowance	1,839	980
Commercial Receivables, excluding Commercial, Financial, and Agricultural [Domain]
Schedule of Impaired Financing Receivables Additional Information [Line Items]
Impaired Financing Receivable, Related Allowance	$ 3,225	$ 2,680