Net Earnings Per Share Net Earnings Per Share (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Net Income (loss) Available to Common Stockholders, Basic	$ 38,807	$ 15,424
Weighted Average Number of Shares Outstanding, Basic	131,183	133,596
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	1,413	1,331
Weighted Average Number of Shares Outstanding, Diluted	132,596	134,927