Stock and Incentive Compensation - Compensation Expense for Awards Under Stock Plan (Details) - Stock and Incentive Compensation Plan [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Recognized compensation expense	$ 1,272	$ 1,158	$ 3,553	$ 3,022
Performance Based Award [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Recognized compensation expense	481	435	1,043	725
Time-Vested Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Recognized compensation expense	$ 791	$ 723	$ 2,510	$ 2,297