Earnings per Share (EPS) and Common Stock - Earnings per Share Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share And Common Stock [Abstract]
Net Income (Loss)	$ 114,445	$ 63,504	$ 180,832	$ 138,539
Weighted-average shares outstanding—Basic	119,587	118,260	119,354	118,037
Dilutive effect of restricted stock units	1,125	781	1,126	875
Weighted-average shares outstanding—Diluted	120,712	119,041	120,480	118,912
Earnings per share—Basic	$ 0.96	$ 0.54	$ 1.52	$ 1.17
Earnings per share—Diluted	$ 0.95	$ 0.53	$ 1.5	$ 1.17