Allowance for collateralized and installment notes receivable (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for Loan and Lease Losses, Adjustments, Other	$ (587)	$ 0
Collateralized receivables, net and Installment Notes Receivables on Manufactured Homes [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	(697)	(377)
Allowance for Loan and Lease Losses, Write-offs	203	678
Allowance for Loan and Lease Losses, Adjustments, Other	(151)	(998)
Total activity	52	(320)
Ending balance	$ (645)	$ (697)

Amount of other addition (reduction) in allowance reserve for credit loss.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
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- Definition

Amount of increase (decrease) of allowance reserve for credit loss.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 210
-Section S99
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