Derivative Instruments - Statement Of Financial Position (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020
Derivative [Line Items]
Derivative asset, net, gross fair value	$ (71,406)		$ (50,970)
Derivative assets, net, net fair value	(71,406)	$ (40,149)	(50,970)	$ (19,470)	$ 2,839	$ 21,921
Current derivative assets
Derivative [Line Items]
Derivative asset, gross fair value	772		186
Derivative asset, amounts netted	(79)		(186)
Derivative assets, net fair value	693		0
Non-current derivative assets
Derivative [Line Items]
Derivative asset, gross fair value	468		228
Derivative asset, amounts netted	(14)		(122)
Derivative assets, net fair value	454		106
Current derivative liabilities
Derivative [Line Items]
Derivative liability, gross fair value	(58,333)		(42,330)
Derivative liability, amounts netted	79		186
Derivative liability, net fair value	(58,254)		(42,144)
Non-current derivative liabilities
Derivative [Line Items]
Derivative liability, gross fair value	(14,313)		(9,054)
Derivative liability, amounts netted	14		122
Derivative liability, net fair value	$ (14,299)		$ (8,932)