Supplemental Guarantor Information - Unaudited Condensed Consolidating Statements of Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	$ (84,530)	$ (54,690)
Cash flows from investing activities:
Capital expenditures	(2,632)	(6,354)
Proceeds from sale of fixed assets	66	54
Return of capital from unconsolidated entities	19	0
Advances to/from subsidiaries	0	0
Net cash used in investing activities	(2,547)	(6,300)
Cash flows from financing activities:
Repayment of debt	(1,150)	(1,479)
Proceeds from issuance of new debt		0
Borrowings from credit facility	125,000	100,000
Repayment of borrowings from credit facility	(95,000)	(75,000)
Debt issuance costs	0	(400)
Repurchase of common stock	0	(16,500)
Tax payments for stock-based compensation awards	(2,646)	(1,850)
Stock option exercises and other financing activities	(1,885)	7
Advances to/from subsidiaries	0	0
Net cash provided by financing activities	24,319	4,778
Decrease in cash, cash equivalents, and restricted cash	(62,758)	(56,212)
Cash, cash equivalents, and restricted cash at beginning of period	122,794	153,248
Cash, cash equivalents, and restricted cash at end of period	60,036	97,036
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
Return of capital from unconsolidated entities	0	0
Advances to/from subsidiaries	21,789	(21,204)
Net cash used in investing activities	21,789	(21,204)
Cash flows from financing activities:
Repayment of debt	0	0
Proceeds from issuance of new debt		0
Borrowings from credit facility	0	0
Repayment of borrowings from credit facility	0	0
Debt issuance costs		0
Repurchase of common stock		0
Tax payments for stock-based compensation awards	0	0
Stock option exercises and other financing activities	0	0
Advances to/from subsidiaries	(21,789)	21,204
Net cash provided by financing activities	(21,789)	21,204
Decrease in cash, cash equivalents, and restricted cash	0	0
Cash, cash equivalents, and restricted cash at beginning of period	0	0
Cash, cash equivalents, and restricted cash at end of period	0	0
Beazer Homes USA, Inc. | Reportable Legal Entities
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	(35,926)	(31,908)
Cash flows from investing activities:
Capital expenditures	0	0
Proceeds from sale of fixed assets	0	0
Return of capital from unconsolidated entities	0	532
Advances to/from subsidiaries	(21,906)	21,204
Net cash used in investing activities	(21,906)	21,736
Cash flows from financing activities:
Repayment of debt	0	(11)
Proceeds from issuance of new debt		0
Borrowings from credit facility	125,000	100,000
Repayment of borrowings from credit facility	(95,000)	(75,000)
Debt issuance costs		(400)
Repurchase of common stock		(16,500)
Tax payments for stock-based compensation awards	(2,646)	(1,850)
Stock option exercises and other financing activities	(1,885)	7
Advances to/from subsidiaries	0	0
Net cash provided by financing activities	25,469	6,246
Decrease in cash, cash equivalents, and restricted cash	(32,363)	(3,926)
Cash, cash equivalents, and restricted cash at beginning of period	85,464	104,796
Cash, cash equivalents, and restricted cash at end of period	53,101	100,870
Guarantor Subsidiaries | Reportable Legal Entities
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	(48,490)	(22,756)
Cash flows from investing activities:
Capital expenditures	(2,632)	(6,354)
Proceeds from sale of fixed assets	66	54
Return of capital from unconsolidated entities	19	0
Advances to/from subsidiaries	0	0
Net cash used in investing activities	(2,547)	(6,300)
Cash flows from financing activities:
Repayment of debt	(1,150)	(1,468)
Proceeds from issuance of new debt		0
Borrowings from credit facility	0	0
Repayment of borrowings from credit facility	0	0
Debt issuance costs		0
Repurchase of common stock		0
Tax payments for stock-based compensation awards	0	0
Stock option exercises and other financing activities	0	0
Advances to/from subsidiaries	21,789	(21,204)
Net cash provided by financing activities	20,639	(22,672)
Decrease in cash, cash equivalents, and restricted cash	(30,398)	(51,728)
Cash, cash equivalents, and restricted cash at beginning of period	37,321	47,877
Cash, cash equivalents, and restricted cash at end of period	6,923	(3,851)
Non-Guarantor Subsidiaries | Reportable Legal Entities
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	(114)	(26)
Cash flows from investing activities:
Capital expenditures	0	0
Proceeds from sale of fixed assets	0	0
Return of capital from unconsolidated entities	0	(532)
Advances to/from subsidiaries	117	0
Net cash used in investing activities	117	(532)
Cash flows from financing activities:
Repayment of debt	0	0
Proceeds from issuance of new debt		0
Borrowings from credit facility	0	0
Repayment of borrowings from credit facility	0	0
Debt issuance costs		0
Repurchase of common stock		0
Tax payments for stock-based compensation awards	0	0
Stock option exercises and other financing activities	0	0
Advances to/from subsidiaries	0	0
Net cash provided by financing activities	0	0
Decrease in cash, cash equivalents, and restricted cash	3	(558)
Cash, cash equivalents, and restricted cash at beginning of period	9	575
Cash, cash equivalents, and restricted cash at end of period	$ 12	$ 17