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Assets Held for Sale - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2021 USD ($) Property	Sep. 30, 2020 USD ($)
Long Lived Assets Held For Sale [Line Items]
Number of Properties | Property	3
Irvine, California Property [Member]
Long Lived Assets Held For Sale [Line Items]
Proceeds from sale of property		$ 14,218,000
Other Current Assets [Member]
Long Lived Assets Held For Sale [Line Items]
Proceeds from sale of property	$ 27,211,000

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Number of properties.

+ References

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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

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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=123570139&loc=d3e3179-108585

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