Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Land Held for Sale	$ 0	$ (168)	$ (38,588)	$ (168)
Total impairment and abandonment charges	0	168	148,618	618
Continuing Operations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges on projects in progress	0	0	110,030	0
Discontinued Operations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Land Held for Sale	0	$ 0	$ 0	(450)
Total impairment and abandonment charges	$ 200			$ 600