Supplemental Guarantor Information - Unaudited Condensed Consolidating Statements of Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	$ (102,224)	$ (62,834)
Cash flows from investing activities:
Capital expenditures	(3,702)	(2,874)
Proceeds from sale of fixed assets	84	46
Investments in unconsolidated entities	(421)	(1,397)
Return of capital from unconsolidated entities	0	1,621
Advances to/from subsidiaries	0	0
Net cash used in investing activities	(4,039)	(2,604)
Cash flows from financing activities:
Repayment of debt	(401,481)	(2,525)
Proceeds from issuance of new debt	400,000	0
Debt issuance costs	(5,649)	(340)
Advances to/from subsidiaries	0	0
Other financing activities	(1,322)	(387)
Net cash used in financing activities	(8,452)	(3,252)
Decrease in cash, cash equivalents and restricted cash	(114,715)	(68,690)
Cash, cash equivalents and restricted cash at beginning of period	304,609	243,276
Cash, cash equivalents and restricted cash at end of period	189,894	174,586
Consolidating Adjustments
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	0	0
Cash flows from investing activities:
Capital expenditures	0	0
Proceeds from sale of fixed assets	0	0
Investments in unconsolidated entities	0	0
Return of capital from unconsolidated entities		0
Advances to/from subsidiaries	187,477	50,314
Net cash used in investing activities	187,477	50,314
Cash flows from financing activities:
Repayment of debt	0	0
Proceeds from issuance of new debt	0
Debt issuance costs	0	0
Advances to/from subsidiaries	(186,563)	(52,222)
Other financing activities	0	0
Net cash used in financing activities	(186,563)	(52,222)
Decrease in cash, cash equivalents and restricted cash	914	(1,908)
Cash, cash equivalents and restricted cash at beginning of period	(7,161)	(4,500)
Cash, cash equivalents and restricted cash at end of period	(6,247)	(6,408)
Beazer Homes USA, Inc.
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	91,465	(2,902)
Cash flows from investing activities:
Capital expenditures	0	0
Proceeds from sale of fixed assets	0	0
Investments in unconsolidated entities	0	0
Return of capital from unconsolidated entities		0
Advances to/from subsidiaries	(187,451)	(50,314)
Net cash used in investing activities	(187,451)	(50,314)
Cash flows from financing activities:
Repayment of debt	(400,012)	0
Proceeds from issuance of new debt	400,000
Debt issuance costs	(5,649)	(340)
Advances to/from subsidiaries	0	0
Other financing activities	(1,322)	(387)
Net cash used in financing activities	(6,983)	(727)
Decrease in cash, cash equivalents and restricted cash	(102,969)	(53,943)
Cash, cash equivalents and restricted cash at beginning of period	294,192	228,513
Cash, cash equivalents and restricted cash at end of period	191,223	174,570
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	(193,721)	(59,928)
Cash flows from investing activities:
Capital expenditures	(3,702)	(2,874)
Proceeds from sale of fixed assets	84	46
Investments in unconsolidated entities	(421)	(1,397)
Return of capital from unconsolidated entities		1,621
Advances to/from subsidiaries	0	0
Net cash used in investing activities	(4,039)	(2,604)
Cash flows from financing activities:
Repayment of debt	(1,469)	(2,525)
Proceeds from issuance of new debt	0
Debt issuance costs	0	0
Advances to/from subsidiaries	186,563	52,224
Other financing activities	0	0
Net cash used in financing activities	185,094	49,699
Decrease in cash, cash equivalents and restricted cash	(12,666)	(12,833)
Cash, cash equivalents and restricted cash at beginning of period	16,854	18,404
Cash, cash equivalents and restricted cash at end of period	4,188	5,571
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	32	(4)
Cash flows from investing activities:
Capital expenditures	0	0
Proceeds from sale of fixed assets	0	0
Investments in unconsolidated entities	0	0
Return of capital from unconsolidated entities		0
Advances to/from subsidiaries	(26)	0
Net cash used in investing activities	(26)	0
Cash flows from financing activities:
Repayment of debt	0	0
Proceeds from issuance of new debt	0
Debt issuance costs	0	0
Advances to/from subsidiaries	0	(2)
Other financing activities	0	0
Net cash used in financing activities	0	(2)
Decrease in cash, cash equivalents and restricted cash	6	(6)
Cash, cash equivalents and restricted cash at beginning of period	724	859
Cash, cash equivalents and restricted cash at end of period	$ 730	$ 853