Allowance for Loan and Lease Losses - Loans that were Evaluated for Impairment by Loan Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Mar. 31, 2016
Unpaid principal balance [Abstract]
With no related allowance recorded	$ 10,197	$ 13,026
With an allowance recorded	5,335	1,732
Recorded investment [Abstract]
With no related allowance recorded	4,777	4,868
With an allowance recorded	2,414	1,598
Related allowance [Abstract]
Related allowance	398	210
Average recorded investment [Abstract]
With no related allowance recorded	9,738
With an allowance recorded	1,965
Interest income recognized [Abstract]
With no related allowance recorded	568
With an allowance recorded	0
Commercial real estate [Member]
Unpaid principal balance [Abstract]
With no related allowance recorded	1,323	2,242
With an allowance recorded	926
Recorded investment [Abstract]
With no related allowance recorded	931	1,368
With an allowance recorded	538
Related allowance [Abstract]
Related allowance	77
Average recorded investment [Abstract]
With no related allowance recorded	4,144
With an allowance recorded	334
Interest income recognized [Abstract]
With no related allowance recorded	335
With an allowance recorded	0
Construction and land development [Member]
Unpaid principal balance [Abstract]
With no related allowance recorded	546	546
With an allowance recorded	0
Recorded investment [Abstract]
With no related allowance recorded	145	145
With an allowance recorded	0
Related allowance [Abstract]
Related allowance	0
Average recorded investment [Abstract]
With no related allowance recorded	376
With an allowance recorded	90
Interest income recognized [Abstract]
With no related allowance recorded	0
With an allowance recorded	0
Commercial and industrial [Member]
Unpaid principal balance [Abstract]
With no related allowance recorded	2,662	4,745
With an allowance recorded	2,500
Recorded investment [Abstract]
With no related allowance recorded	2,576	2,317
With an allowance recorded	111
Related allowance [Abstract]
Related allowance	100
Average recorded investment [Abstract]
With no related allowance recorded	4,314
With an allowance recorded	172
Interest income recognized [Abstract]
With no related allowance recorded	233
With an allowance recorded	0
Residential real estate [Member]
Unpaid principal balance [Abstract]
With an allowance recorded	1,033	977
Recorded investment [Abstract]
With an allowance recorded	889	843
Related allowance [Abstract]
Related allowance	27	25
Average recorded investment [Abstract]
With an allowance recorded	938
Interest income recognized [Abstract]
With an allowance recorded	0
Leases [Member]
Unpaid principal balance [Abstract]
With an allowance recorded	876	755
Recorded investment [Abstract]
With an allowance recorded	876	755
Related allowance [Abstract]
Related allowance	194	185
Average recorded investment [Abstract]
With an allowance recorded	243
Interest income recognized [Abstract]
With an allowance recorded	0
Tax certificates [Member]
Unpaid principal balance [Abstract]
With no related allowance recorded	5,666	5,493
With an allowance recorded	0
Recorded investment [Abstract]
With no related allowance recorded	1,125	$ 1,038
With an allowance recorded	0
Related allowance [Abstract]
Related allowance	0
Average recorded investment [Abstract]
With no related allowance recorded	904
With an allowance recorded	188
Interest income recognized [Abstract]
With no related allowance recorded	0
With an allowance recorded	$ 0