Business and Organization (Details) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2020 vote	Oct. 31, 2020 USD ($) $ / shares	Sep. 30, 2020 vote	Sep. 30, 2020 USD ($)	Sep. 30, 2020 member	Sep. 30, 2020 numberOfHomesites	Sep. 30, 2020 ft²	Sep. 30, 2020 a	Aug. 31, 2017 building
Class of Stock [Line Items]
Number of votes per share	1
Right to exchange, conversion ratio	1
Number of voting members | member					3
Number of votes of management			5
Percentage of voting members required for approval	75.00%
Number of votes of company			2
Number of votes for each member			1
Area of Gateway campus | ft²							1,000,000
Number of buildings on campus						4			4
Area of land (in acres)							73	50
Number of buildings on campus | numberOfHomesites						4
Great Park
Class of Stock [Line Items]
Percentage of equity ownership	37.50%
Number of voting members | member					4
Heritage Fields LLC
Class of Stock [Line Items]
Percentage of equity ownership	37.50%
Subsequent Event
Class of Stock [Line Items]
Closing price (in dollars per share) | $ / shares		$ 4.19
The San Francisco Venture
Class of Stock [Line Items]
Right to exchange, conversion ratio	1
Equity Method Investee | Great Park | Contingent Payments Due from Related Parties
Class of Stock [Line Items]
Related party assets | $				$ 565.0
Equity Method Investee | Subsequent Event | Great Park | Legacy Incentive Compensation Receivable
Class of Stock [Line Items]
Distributions to holders of legacy interests | $		$ 431.3
Five Point Operating Company, LLC | Affiliated Entity | The San Francisco Venture
Class of Stock [Line Items]
Right to exchange, conversion ratio	1
Percentage of distributions entitled to receive	99.00%
FPOVHI Member, LLC | Five Point Office Venture Holdings I, LLC Acquisition
Class of Stock [Line Items]
Percentage of equity ownership	75.00%
Percentage of equity ownership	75.00%
Five Point Land, LLC | Subsidiary of Common Parent
Class of Stock [Line Items]
Subsidiary ownership	100.00%
San Francisco Venture | Subsidiary of Common Parent
Class of Stock [Line Items]
Subsidiary ownership	100.00%
Gateway Commercial Venture
Class of Stock [Line Items]
Number of buildings on campus | numberOfHomesites						1
Parent Company | Five Point Operating Company, LLC | Affiliated Entity
Class of Stock [Line Items]
Right to exchange, conversion ratio	1
Parent Company | Five Point Operating Company, LLC | Affiliated Entity | Five Point Operating Company, LLC
Class of Stock [Line Items]
Ownership of class A common stock, percentage	62.50%
Parent Company | Five Point Operating Company, LLC | Affiliated Entity | Subsequent Event
Class of Stock [Line Items]
Market capitalization of company | $		$ 621.4
Common Class B
Class of Stock [Line Items]
Conversion of common shares, ratio	0.0003