Loans Receivable and Allowance for Loan Losses (Schedule of Impaired Loan Receivables, Average) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Loans With No Related Allowance:
Average Recorded Investment	$ 38,449	$ 43,122	$ 39,238	$ 45,121
Interest Income Recognized	215	339	685	921
Loans With An Allowance Recorded:
Average Recorded Investment	23,532	21,666	20,697	18,697
Interest Income Recognized	0	0	0	0
Total Impaired Loans:
Average Recorded Investment	61,981	64,788	59,935	63,818
Interest Income Recognized	215	339	685	921
Commercial and industrial [Member]
Loans With No Related Allowance:
Average Recorded Investment	9,501	11,921	9,320	12,042
Interest Income Recognized	47	48	121	140
Loans With An Allowance Recorded:
Average Recorded Investment	4,587	8,106	5,030	4,709
Interest Income Recognized	0	0	0	0
Total Impaired Loans:
Average Recorded Investment	14,088	20,027	14,350	16,751
Interest Income Recognized	47	48	121	140
Commercial tax-exempt [Member]
Loans With No Related Allowance:
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Total Impaired Loans:
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Owner occupied real estate [Member]
Loans With No Related Allowance:
Average Recorded Investment	3,808	2,379	2,841	4,465
Interest Income Recognized	0	27	0	150
Loans With An Allowance Recorded:
Average Recorded Investment	1,399	2,036	1,418	1,436
Interest Income Recognized	0	0	0	0
Total Impaired Loans:
Average Recorded Investment	5,207	4,415	4,259	5,901
Interest Income Recognized	0	27	0	150
Commercial construction and land development [Member]
Loans With No Related Allowance:
Average Recorded Investment	6,366	9,682	7,399	10,668
Interest Income Recognized	43	166	133	417
Loans With An Allowance Recorded:
Average Recorded Investment	8,848	11,524	8,168	12,552
Interest Income Recognized	0	0	0	0
Total Impaired Loans:
Average Recorded Investment	15,214	21,206	15,567	23,220
Interest Income Recognized	43	166	133	417
Commercial real estate [Member]
Loans With No Related Allowance:
Average Recorded Investment	10,229	12,238	11,550	11,699
Interest Income Recognized	104	79	360	175
Loans With An Allowance Recorded:
Average Recorded Investment	5,129	0	4,486	0
Interest Income Recognized	0	0	0	0
Total Impaired Loans:
Average Recorded Investment	15,358	12,238	16,036	11,699
Interest Income Recognized	104	79	360	175
Residential [Member]
Loans With No Related Allowance:
Average Recorded Investment	5,355	4,270	4,942	3,946
Interest Income Recognized	13	13	49	31
Loans With An Allowance Recorded:
Average Recorded Investment	3,091	0	1,381	0
Interest Income Recognized	0	0	0	0
Total Impaired Loans:
Average Recorded Investment	8,446	4,270	6,323	3,946
Interest Income Recognized	13	13	49	31
Consumer [Member]
Loans With No Related Allowance:
Average Recorded Investment	3,190	2,632	3,186	2,301
Interest Income Recognized	8	6	22	8
Loans With An Allowance Recorded:
Average Recorded Investment	478	0	214	0
Interest Income Recognized	0	0	0	0
Total Impaired Loans:
Average Recorded Investment	3,668	2,632	3,400	2,301
Interest Income Recognized	$ 8	$ 6	$ 22	$ 8