Marketable Securities	9 Months Ended
Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	Marketable SecuritiesAs of September 30, 2021 and December 31, 2020, we owned 564,612 common shares of The Macerich Company (“Macerich”) (NYSE: MAC). As of September 30, 2021 and December 31, 2020, the fair value of these shares was $9,435,000 and $6,024,000, respectively, based on Macerich’s closing share price of $16.71 per share and $10.67 per share, respectively. These shares are presented at fair value as “marketable securities” on our consolidated balance sheets and the gains and losses resulting from the mark-to-market of these securities are recognized in current period earnings.

The entire disclosure for investments in certain debt and equity securities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-URI http://asc.fasb.org/subtopic&trid=2209399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-URI http://asc.fasb.org/subtopic&trid=2324412

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-URI http://asc.fasb.org/topic&trid=2196928

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-URI http://asc.fasb.org/subtopic&trid=2176304

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1403
-Paragraph (b)

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