Other Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015
Other Liabilities Disclosure [Abstract]
Accrued warranty expense	$ 25,386	$ 32,309	$ 39,131	$ 40,903	$ 28,913	$ 27,681
Accrued bonuses and deferred compensation	17,497		30,466
Customer deposits	14,579		12,140
Accrued interest	11,664		11,530
Litigation accrual	3,992		10,178
Income tax liabilities	1,897		1,718
Other	27,512		29,090
Total other liabilities	$ 102,527		$ 134,253