Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

Goodwill (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020	Mar. 31, 2018
Business Acquisition [Line Items]
Goodwill	$ 16.4	$ 16.4
Pinnacle Homes [Member]
Business Acquisition [Line Items]
Goodwill			$ 16.4