Stock Based Compensation - Schedule of Pre-tax Expense Associated with All Outstanding Non-vested RSAs, RSUs, Performance Based Restricted Stock Units and Related Tax Benefits (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share Based Compensation [Abstract]
Stock based compensation expense	$ 699	$ 807	$ 1,318	$ 1,347
Related tax benefits	$ 197	$ 227	$ 370	$ 379