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Notes and Other Receivables (Details) - USD ($)	1 Months Ended	9 Months Ended
Notes and Other Receivables (Details) - USD ($)	Jan. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable		$ 75,432,000	$ 134,365,000
Notes and other receivables, allowance for credit loss		(172,000)	0
Notes receivable, secured, bearing interest at 9.00%, due May 2021 (Originated May 2017)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable		$ 0	16,828,000
Stated interest rate		9.00%
Note receivable, secured, bearing interest at 9.90%, due November 2021 (Originated November 2018)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable		$ 13,857,000	12,838,000
Stated interest rate		9.90%
Related party note receivable, secured, bearing variable rate interest, due February 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable		$ 0	85,713,000
Notes receivable, secured, bearing interest at 10.50%, due February 2023 (Originated March 2020)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable		$ 7,499,000	0
Stated interest rate		10.50%
Note receivable, secured, bearing interest at 11.00%, due October 2023 (Originated April 2020)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable		$ 13,134,000	0
Stated interest rate		11.00%
Notes and other receivables from affiliates
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable		$ 5,505,000	4,442,000
Straight line rent receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable		21,373,000	6,083,000
Other receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable		$ 14,236,000	$ 8,461,000
Affiliated Entity \| Notes receivable, secured, bearing interest at 9.00%, due May 2021 (Originated May 2017)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from redemption of notes receivable	$ 16,900,000
Affiliated Entity \| Related party note receivable, secured, bearing variable rate interest, due February 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from redemption of notes receivable	$ 85,800,000