Fair Value of Financial Instruments , By Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Financial assets
Notes and other receivables, net	$ 145,760	$ 81,179
Collateralized receivables, net	134,015	143,870
Financial liabilities
Secured debt	2,822,640	2,819,567
Lines of credit		100,095
Carrying Value [Member]
Financial liabilities
Debt (excluding secured borrowings)	2,868,543	2,865,470
Lines of credit		100,095
Other liabilities (contingent consideration)	11,115	10,011
Carrying Value [Member] \| Installment notes receivable on manufactured homes, net [Member]
Financial assets
Notes and other receivables, net		59,320
Carrying Value [Member] \| Collateralized Receivables [Member]
Financial assets
Notes and other receivables, net	134,000	143,870
Carrying Value [Member] \| Secured Debt [Member]
Financial liabilities
Secured borrowings on collateralized receivables		144,477
Secured debt	134,884	144,477
Estimate of Fair Value Measurement [Member] \| Fair Value, Measurements, Recurring [Member]
Financial liabilities
Debt (excluding secured borrowings)	2,837,449	2,820,680
Secured borrowings on collateralized receivables	134,884
Secured debt		144,477
Lines of credit	0
Lines of credit		98,640
Other liabilities (contingent consideration)	11,115	10,011
Estimate of Fair Value Measurement [Member] \| Installment notes receivable on manufactured homes, net [Member] \| Fair Value, Measurements, Recurring [Member]
Financial assets
Notes and other receivables, net	97,990
Receivables		59,320
Estimate of Fair Value Measurement [Member] \| Collateralized Receivables [Member] \| Fair Value, Measurements, Recurring [Member]
Financial assets
Receivables		$ 143,870
Collateralized receivables, net	$ 134,015

Long term debt excluding secured borrowings, Fair Value Disclosure

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- Definition

Carrying amount as of the balance sheet date, net of allowance for doubtful accounts, of account and note receivables due from other than related parties.

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- References

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ 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(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 942
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Fair value portion of contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time.

+ References

No definition available.

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- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(c))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

+ References

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- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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- Definition

Fair value portion of other liabilities.

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: 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(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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