The number of communities sold by the entity during the period.

No definition available.

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- Definition

The number of units sold by the entity during the period.

+ References

No definition available.

+ Details

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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2443-110228

+ Details

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Balance Type:	credit
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- 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

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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Real Estate Investments - Sales of Real Estate Investments (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) community unit	Dec. 31, 2017 USD ($) community unit
Communities Sold in 2019 \| Santa Mateo, CA
Real Estate Properties [Line Items]
Gain (loss) on sale of properties	$ (3.2)
Communities Sold in 2019 \| Rental and Other Property \| Santa Clara, CA
Real Estate Properties [Line Items]
Total property revenues	10.8
Communities Sold in 2019 \| Rental and Other Property \| Santa Mateo, CA
Real Estate Properties [Line Items]
Total property revenues	$ 12.5
Communities Sold in 2018
Real Estate Properties [Line Items]
Number of communities sold \| community		2
Number of units sold \| unit		669
Gain (loss) on sale of properties		$ 61.9
Communities Sold in 2018 \| Rental and Other Property
Real Estate Properties [Line Items]
Total property revenues		$ 352.0
Communities Sold in 2017
Real Estate Properties [Line Items]
Number of communities sold \| community			1
Number of units sold \| unit			270
Gain (loss) on sale of properties			$ 26.2
Communities Sold in 2017 \| Rental and Other Property
Real Estate Properties [Line Items]
Total property revenues			$ 132.5