Loans Receivable and Allowance for Loan Losses (Summary of Nonaccrual Loans, by Type) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment [Line Items]
Period used to determine when a loan receivable is moved to nonaccrual status	90 days
Nonaccrual loans	$ 33,167	$ 39,963
Loans receivable, equal to greater than 90 days past due	19,988	21,701
Nonaccrual loans, unused commitment	0
Commercial and industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans	7,974	10,217
Loans receivable, equal to greater than 90 days past due	3,954	5,751
Commercial tax-exempt [Member]
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans	0	0
Loans receivable, equal to greater than 90 days past due	0	0
Owner occupied real estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans	6,954	4,838
Loans receivable, equal to greater than 90 days past due	5,640	2,847
Commercial construction and land development [Member]
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans	3,254	8,587
Loans receivable, equal to greater than 90 days past due	0	5,239
Commercial real estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans	6,407	6,705
Loans receivable, equal to greater than 90 days past due	3,940	4,837
Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans	6,157	7,039
Loans receivable, equal to greater than 90 days past due	4,517	1,916
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans	2,421	2,577
Loans receivable, equal to greater than 90 days past due	$ 1,937	$ 1,111