Net Income Per Common Share (Schedule of Basic and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Basic Net Income Per Common Share:
Net income available to common shareholders	$ 83,283	$ 127,435	$ 198,414	$ 397,505
Weighted average common shares outstanding (in shares)	147,314	152,238	147,304	156,819
Net income per common share, basic (in dollars per share)	$ 0.57	$ 0.84	$ 1.35	$ 2.53
Diluted Net Income Per Common Share:
Net income available to common shareholders	$ 83,283	$ 127,435	$ 198,414	$ 397,505
Weighted average common shares outstanding (in shares)	147,314	152,238	147,304	156,819
Effect of dilutive outstanding equity-based awards, warrants, and earnout payments (in shares)	662	1,805	733	1,776
Weighted average number of diluted common shares (in shares)	147,976	154,043	148,037	158,595
Net income per common share, diluted (in dollars per share)	$ 0.56	$ 0.83	$ 1.34	$ 2.51