Inventory - Summary of Interests in Lot Option Agreements (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Sep. 30, 2015
Real Estate Properties [Line Items]
Land not owned under option agreements		$ 0
Unconsolidated lot option agreements
Real Estate Properties [Line Items]
Deposits and non-refundable preacquisition costs incurred	$ 65,552	51,475
Remaining obligations	$ 421,098	$ 420,070

Land Under Purchase Options, Consolidated and Unconsolidated VIEs, Total Remaining Obligations Under Option Agreements

No definition available.

Name:	bzh_LandUnderPurchaseOptionsConsolidatedAndUnconsolidatedViesTotalRemainingObligationsUnderOptionAgreements
Namespace Prefix:	bzh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Land Under Purchase Options, Deposits and Non-refundable Preacquisition Costs

+ References

No definition available.

+ Details

Name:	bzh_LandUnderPurchaseOptionsDepositsAndNonRefundablePreacquisitionCosts
Namespace Prefix:	bzh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The carrying amount as of the balance sheet date of land not owned but under a contract in which the entity has an option to purchase the land.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LandUnderPurchaseOptionsRecorded
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_RealEstatePropertiesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=bzh_UnconsolidatedEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: