Stock-Based Compensation Stock-Based Compensation Expense (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Income tax benefit	$ (111)	$ (126)	$ (222)	$ (241)
Net stock-based compensation expense	180	202	359	389
Personnel costs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	156	204	315	388
Other operating expenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	$ 135	$ 124	$ 266	$ 242