Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands						3 Months Ended		9 Months Ended
	Aug. 04, 2017	May 02, 2017	Feb. 09, 2017	Oct. 28, 2016	Aug. 02, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Dividends [Abstract]
Dividend per Common Share	$ 0.26	$ 0.26	$ 0.26	$ 0.26	$ 0.24	$ 0.26	$ 0.24	$ 0.78	$ 0.72
Aggregate Dividend Amount	$ 20,464	$ 20,482	$ 20,466	$ 20,434	$ 18,872