Allowance for Loan and Lease Losses - Loans that were Evaluated for Impairment by Loan Segment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Sep. 30, 2014
Unpaid principal balance [Abstract]
With no related allowance recorded	$ 21,151	$ 23,609
With an allowance recorded	9,315	8,805
Recorded investment [Abstract]
With no related allowance recorded	14,671	11,909
With an allowance recorded	3,835	4,232
Related allowance [Abstract]
Related allowance	886	493
Average recorded investment [Abstract]
With no related allowance recorded	18,100
With an allowance recorded	5,655
Interest income recognized [Abstract]
With no related allowance recorded	559
Commercial real estate [Member]
Unpaid principal balance [Abstract]
With no related allowance recorded	4,429	7,410
With an allowance recorded	1,435	1,137
Recorded investment [Abstract]
With no related allowance recorded	4,158	5,986
With an allowance recorded	1,435	891
Related allowance [Abstract]
Related allowance	331	205
Average recorded investment [Abstract]
With no related allowance recorded	7,956
With an allowance recorded	1,879
Interest income recognized [Abstract]
With no related allowance recorded	73
Construction and land development [Member]
Unpaid principal balance [Abstract]
With no related allowance recorded	9,850	2,690
With an allowance recorded		559
Recorded investment [Abstract]
With no related allowance recorded	3,907	633
With an allowance recorded		559
Related allowance [Abstract]
Related allowance		172
Average recorded investment [Abstract]
With no related allowance recorded	3,933
With an allowance recorded	381
Interest income recognized [Abstract]
With no related allowance recorded	209
Commercial and industrial [Member]
Unpaid principal balance [Abstract]
With no related allowance recorded	6,693	8,133
With an allowance recorded	2,592	1,721
Recorded investment [Abstract]
With no related allowance recorded	6,491	4,400
With an allowance recorded	1,290	1,497
Related allowance [Abstract]
Related allowance	452	5
Average recorded investment [Abstract]
With no related allowance recorded	5,960
With an allowance recorded	2,456
Interest income recognized [Abstract]
With no related allowance recorded	250
Residential real estate [Member]
Unpaid principal balance [Abstract]
With an allowance recorded	827	1,080
Recorded investment [Abstract]
With an allowance recorded	631	983
Related allowance [Abstract]
Related allowance	19	30
Average recorded investment [Abstract]
With no related allowance recorded	84
With an allowance recorded	492
Interest income recognized [Abstract]
With no related allowance recorded	27
Leases [Member]
Unpaid principal balance [Abstract]
With an allowance recorded	139	64
Recorded investment [Abstract]
With an allowance recorded	139	64
Related allowance [Abstract]
Related allowance	60	62
Average recorded investment [Abstract]
With an allowance recorded	106
Tax certificates [Member]
Unpaid principal balance [Abstract]
With no related allowance recorded	179	5,376
With an allowance recorded	4,322	4,244
Recorded investment [Abstract]
With no related allowance recorded	115	890
With an allowance recorded	340	238
Related allowance [Abstract]
Related allowance	24	19
Average recorded investment [Abstract]
With no related allowance recorded	167
With an allowance recorded	$ 341