Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Basic and Diluted Earnings Per Share, Continuing Operations [Abstract]
Net Income	$ 157,646	$ 314,132
Income allocated to participating securities	135	328
Income available to common shareholders	$ 157,511	$ 313,804
Basic weighted average shares outstanding	113,800	108,564
Basic net income per share	$ 1.38	$ 2.89
Effect of dilutive shares	$ 0	$ 0
Income available to common shareholders, diluted	$ 157,511	$ 313,804
Additional dilutive shares	32	0
Diluted weighted average shares outstanding	113,832	108,564
Diluted net income per share	$ 1.38	$ 2.89