Earnings per Share (EPS) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Net income (in usd)									$ 87,717	$ 83,062	$ 50,518
Weighted average shares outstanding	79,682,724	79,700,403	79,669,922	79,658,583	80,258,489	80,315,050	80,184,977	77,879,593	79,679,781	79,669,668	74,459,508
Effect of dilutive securities									177,140	239,583	351,900
Adjusted weighted average shares outstanding	79,845,447	79,883,510	79,886,292	79,843,578	80,407,558	80,515,467	80,505,614	78,167,800	79,856,921	79,909,251	74,811,408
Basic EPS (in dollars per share)	$ 0.28	$ 0.28	$ 0.26	$ 0.28	$ 0.26	$ 0.28	$ 0.26	$ 0.24	$ 1.10	$ 1.04	$ 0.68
Diluted EPS (in dollars per share)	$ 0.28	$ 0.28	$ 0.26	$ 0.28	$ 0.26	$ 0.28	$ 0.26	$ 0.24	$ 1.10	$ 1.04	$ 0.68