Loans Receivable and Allowance for Loan Losses (Schedule of Impaired Loan Receivables, Average) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Loans With No Related Allowance:
Average Recorded Investment	$ 38,810	$ 38,978
Interest Income Recognized	135	244
Loans With An Allowance Recorded:
Average Recorded Investment	11,964	18,639
Interest Income Recognized	0	0
Total Impaired Loans:
Average Recorded Investment	50,774	57,617
Interest Income Recognized	135	244
Commercial and industrial [Member]
Loans With No Related Allowance:
Average Recorded Investment	7,890	8,508
Interest Income Recognized	40	31
Loans With An Allowance Recorded:
Average Recorded Investment	3,246	5,190
Interest Income Recognized	0	0
Total Impaired Loans:
Average Recorded Investment	11,136	13,698
Interest Income Recognized	40	31
Commercial tax-exempt [Member]
Loans With No Related Allowance:
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Total Impaired Loans:
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Owner occupied real estate [Member]
Loans With No Related Allowance:
Average Recorded Investment	4,786	1,951
Interest Income Recognized	10	0
Loans With An Allowance Recorded:
Average Recorded Investment	1,686	1,436
Interest Income Recognized	0	0
Total Impaired Loans:
Average Recorded Investment	6,472	3,387
Interest Income Recognized	10	0
Commercial construction and land development [Member]
Loans With No Related Allowance:
Average Recorded Investment	8,241	8,023
Interest Income Recognized	17	45
Loans With An Allowance Recorded:
Average Recorded Investment	3,477	7,842
Interest Income Recognized	0	0
Total Impaired Loans:
Average Recorded Investment	11,718	15,865
Interest Income Recognized	17	45
Commercial real estate [Member]
Loans With No Related Allowance:
Average Recorded Investment	10,770	12,862
Interest Income Recognized	48	145
Loans With An Allowance Recorded:
Average Recorded Investment	0	4,171
Interest Income Recognized	0	0
Total Impaired Loans:
Average Recorded Investment	10,770	17,033
Interest Income Recognized	48	145
Residential [Member]
Loans With No Related Allowance:
Average Recorded Investment	4,488	4,572
Interest Income Recognized	13	17
Loans With An Allowance Recorded:
Average Recorded Investment	3,079	0
Interest Income Recognized	0	0
Total Impaired Loans:
Average Recorded Investment	7,567	4,572
Interest Income Recognized	13	17
Consumer [Member]
Loans With No Related Allowance:
Average Recorded Investment	2,635	3,062
Interest Income Recognized	7	6
Loans With An Allowance Recorded:
Average Recorded Investment	476	0
Interest Income Recognized	0	0
Total Impaired Loans:
Average Recorded Investment	3,111	3,062
Interest Income Recognized	$ 7	$ 6