Stock Based Compensation - Expense Table (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	$ 1,484	$ 1,344	$ 3,169	$ 2,732
Stock Options Compensation Expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	199	171	384	321
Nonvested Stock Awards and Restricted Stock Unit Compensation Expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	759	609	1,511	1,165
Employee Stock Purchase Plan Compensation Expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	19	19	37	36
401 (k) Matching Stock Contribution Plan Compensation Expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	476	499	1,175	1,148
Directors Stock Ownership Plan Compensation Expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	$ 31	$ 46	$ 62	$ 62