Other Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2015
Other Liabilities Disclosure [Abstract]
Accrued interest	$ 25,890		$ 11,530
Accrued bonuses and deferred compensation	25,740		30,466
Accrued warranty expense	19,822	$ 25,386	39,131	$ 40,590	$ 40,903	$ 27,681
Customer deposits	16,032		12,140
Litigation accrual	4,351		10,178
Income tax liabilities	2,344		1,718
Other	25,475		29,090
Total other liabilities	$ 119,654		$ 134,253