Area of land held.

No definition available.

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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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.

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- Definition

Net rentable area for properties owned.

+ References

No definition available.

+ Details

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The cash inflow from the sale of formerly productive land held for sale, anything permanently fixed to it, including buildings, structures on it, and so forth.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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Dispositions - Operating Property Dispositions (Details) $ in Thousands	1 Months Ended						12 Months Ended
	Oct. 31, 2019 USD ($) ft² property	May 31, 2019 USD ($) ft² property	Dec. 31, 2018 USD ($) ft² property	Nov. 30, 2018 USD ($) ft² property	Sep. 30, 2017 USD ($) ft² a property	Jan. 31, 2017 USD ($) ft² property	Dec. 31, 2019 USD ($) ft² property	Dec. 31, 2018 USD ($) ft² property	Dec. 31, 2017 USD ($) ft² property
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Rentable square feet \| ft²							13,475,795
Gains on sales of operating properties \| $							$ 36,802	$ 142,926	$ 39,507
Disposal group, disposed of by sale [Member] \| 2829 Townsgate Road, Thousand Oaks, CA and 2211 Michelson Drive, Irvine, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings \| property							2
Rentable square feet \| ft²							355,654
Proceeds from sale of property held-for-sale \| $							$ 133,800
Disposal group, disposed of by sale [Member] \| 2829 Townsgate Road, Thousand Oaks, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings \| property		1
Rentable square feet \| ft²		84,098
Proceeds from sale of property held-for-sale \| $		$ 18,300
Disposal group, disposed of by sale [Member] \| 2211 Michelson Drive Irvine CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings \| property	1
Rentable square feet \| ft²	271,556
Proceeds from sale of property held-for-sale \| $	$ 115,500
Disposal group, disposed of by sale [Member] \| 1310-1327 Chesapeake Terrace, Sunnyvale, CA , Plaza Yarrow Bay Properties, and 23925, 23975, & 24025 Park Sorrento, Calabasas, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings \| property			11					11
Rentable square feet \| ft²			772,246					772,246
Proceeds from sale of property held-for-sale \| $								$ 373,000
Disposal group, disposed of by sale [Member] \| 1325-1327 Chesapeake Terrace, Sunnyvale, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings \| property				4
Rentable square feet \| ft²				266,982
Proceeds from sale of property held-for-sale \| $				$ 160,300
Disposal group, disposed of by sale [Member] \| Plaza Yarrow Bay Properties [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings \| property				4
Rentable square feet \| ft²				279,924
Proceeds from sale of property held-for-sale \| $				$ 134,500
Disposal group, disposed of by sale [Member] \| 23925, 23975, & 24025 Park Sorrento, Calabasas, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings \| property			3					3
Rentable square feet \| ft²			225,340					225,340
Proceeds from sale of property held-for-sale \| $			$ 78,200
Disposal group, disposed of by sale [Member] \| 5717 Pacific Center Boulevard, San Diego, CA and Sorrento Mesa and Mission Valley Portfolio [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings \| property									11
Rentable square feet \| ft²									743,138
Proceeds from sale of property held-for-sale \| $									$ 186,600
Disposal group, disposed of by sale [Member] \| 5717 Pacific Center Boulevard, San Diego, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings \| property						1
Rentable square feet \| ft²						67,995
Proceeds from sale of property held-for-sale \| $						$ 12,100
Disposal group, disposed of by sale [Member] \| Sorrento Mesa and Mission Valley Properties [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of buildings \| property					10
Rentable square feet \| ft²					675,143
Proceeds from sale of property held-for-sale \| $					$ 174,500
Area of land \| a					5.0