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Investments in Equity Affiliates - All Investments (Details) | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jan. 31, 2021 | Dec. 31, 2021 USD ($) item | Jun. 30, 2021 USD ($) | Mar. 31, 2021 USD ($) | Dec. 31, 2021 USD ($) item | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2015 USD ($) | Sep. 30, 2021 USD ($)
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Income from equity affiliates |  |  |  |  | $ 34,567,000 | $ 76,161,000 | $ 10,635,000 |  |  |
Indirect ownership percentage |  |  |  |  | 9.20% |  |  |  |  |
Noncontrolling interest invested |  |  |  |  | $ 48,071,000 | 892,000 | 13,522,000 |  |  |
Arbor Residential Investor LLC |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Income from equity affiliates |  |  |  |  | 34,600,000 | 75,700,000 |  | $ 7,200,000 |  |
Distribution received |  |  |  |  | 28,000,000.0 | 43,200,000 |  |  |  |
Equity Investment |  |  |  |  |  |  |  |  | $ 9,600,000 |
Percentage of ownership interest of related party in the entity |  |  |  |  |  |  |  |  | 50.00% |
Arbor Residential Investor LLC | Minimum |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Indirect ownership percentage | 12.30% |  |  |  |  |  |  |  |  |
Arbor Residential Investor LLC | Maximum |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Indirect ownership percentage | 16.30% |  |  |  |  |  |  |  |  |
Arbor Residential Investor LLC | Wakefield Investment Holdings Llc [Member] |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Percentage of ownership interest of related party in the entity |  |  |  |  |  |  |  |  | 50.00% |
Residential mortgage banking business |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Indirect ownership percentage |  |  |  |  |  |  |  |  | (65.00%) |
AMAC Holdings III LLC |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Income from equity affiliates |  |  |  |  | 1,300,000 | 900,000 |  |  |  |
Distribution received |  |  |  |  | 3,800,000 | 100,000 |  |  |  |
Investment in real estate committed |  |  |  |  |  | $ 30,000,000.0 |  |  |  |
Investment in real estate |  | $ 20,300,000 |  |  | 20,300,000 |  |  |  |  |
Interest in a real estate investment (as a percent) |  |  |  |  |  | 18.00% |  |  |  |
Fifth Wall Ventures III |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Investment in real estate committed |  | 25,000,000.0 |  |  |  |  |  |  |  |
Investment in real estate |  | 5,400,000 |  |  | $ 5,400,000 |  |  |  |  |
Interest in a real estate investment (as a percent) |  |  |  |  | 7.60% |  |  |  |  |
Number of investments |  |  |  |  | 2 |  |  |  |  |
North Vermont Avenue |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Noncontrolling interest invested |  |  |  |  |  | $ 2,400,000 |  |  |  |
Noncontrolling interest in equity method investment (as a percent) |  |  |  |  |  | 85.00% |  |  |  |
Lightstone Value Plus REIT L.P. |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Equity Investment |  | $ 1,900,000 |  |  | $ 1,900,000 |  |  |  |  |
West Shore Cafe |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Ownership percentage |  | 50.00% |  |  | 50.00% |  |  |  |  |
Provided first mortgage loan to an affiliated entity |  |  |  |  | $ 1,700,000 |  |  |  |  |
Variable rate, spread (as a percent) |  |  |  |  | 4.00% |  |  |  |  |
Other-than-temporary impairment recorded |  |  |  |  |  |  | 2,200,000 |  |  |
Provision for loan loss recorded |  |  |  |  |  |  | $ 1,700,000 |  |  |
JT Prime |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Equity Investment |  | $ 400,000 |  |  | $ 400,000 |  |  |  |  |
Noncontrolling interest in equity method investment (as a percent) |  |  |  |  | 50.00% |  |  |  |  |
Century Summerfield Apartments |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Income from equity affiliates |  |  | $ 200,000 |  |  |  |  |  |  |
Distribution received |  |  | $ 17,200,000 |  |  |  |  |  |  |
Investment in real estate committed |  |  |  | $ 20,000,000.0 |  |  |  |  |  |
Investment in real estate |  |  |  | $ 17,000,000.0 |  |  |  |  |  |
Ownership percentage |  |  |  | 50.00% |  |  |  |  |  |
Tapestry on the River |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Income from equity affiliates |  | 700,000 |  |  |  |  |  |  |  |
Distribution received |  | 14,700,000 |  |  |  |  |  |  |  |
Investment in real estate |  |  |  |  |  |  |  |  |  | $ 14,000,000.0
Ownership percentage |  |  |  |  |  |  |  |  |  | 48.90%
Emerson at Forney |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Income from equity affiliates |  | 200,000 |  |  |  |  |  |  |  |
Distribution received |  | $ 3,200,000 |  |  |  |  |  |  |  |
Investment in real estate |  |  |  |  |  |  |  |  |  | $ 3,000,000.0
Ownership percentage |  |  |  |  |  |  |  |  |  | 11.10%
Lexford Portfolio |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Distribution received |  |  |  |  | $ 1,100,000 | $ 3,500,000 |  |  |  |
Noncontrolling interest |  |  |  |  | 100,000 |  |  |  |  |
East River Portfolio |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Equity investment made |  |  |  |  | $ 100,000 |  |  |  |  |
Ownership percentage |  | 5.00% |  |  | 5.00% |  |  |  |  |
Number of Real Estate Properties | item |  | 2 |  |  | 2 |  |  |  |  |
East River Portfolio | Chief executive officer and other related parties |  |  |  |  |  |  |  |  |  |
Investment in Equity Affiliates |  |  |  |  |  |  |  |  |  |
Percentage of ownership interest of related party in the entity |  |  |  |  | 95.00% |  |  |  |  |

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- Definition The cash outflow associated with the purchase of or advances to equity method investments by the company, along with a consortium of independent outside investors. + References No definition available. + Details
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- Definition Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities. + 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=123570139&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(10)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(12)) -URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21D -URI http://asc.fasb.org/extlink&oid=123570139&loc=SL94080555-108585 + Details
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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=124268079&loc=d3e32787-111569 + Details
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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 25 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8813-108599 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition The cash outflow from advancing money to an affiliate (an entity that is related but not strictly controlled by the entity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3213-108585 + Details
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