Mortgage And Other Notes Receivable (Schedule of Financing Receivables, Allowance for Credit Loss Roll Forward) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Beginning Balance	$ 4,946
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	193
Financing Receivable, Allowance for Credit Loss, Ending Balance	5,139
Loans and Leases Receivable, Gross	289,747
Mortgages [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	224,186
Mortgages [Member] \| EBITDARM Coverage Below 1.0x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	53,083
Mortgages [Member] \| EBITDARM Coverage above 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	62,497
Mortgages [Member] \| EBITDARM Coverage, 1.0x to 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	108,606
Mezzanine
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	51,521
Mezzanine \| EBITDARM Coverage Below 1.0x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	14,500
Mezzanine \| EBITDARM Coverage above 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	3,566
Mezzanine \| EBITDARM Coverage, 1.0x to 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	32,705
Mezzanine \| EBITDARM Coverage Not Available
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	750
Revolving Credit Facility
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	14,040
Revolving Credit Facility \| EBITDARM Coverage above 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	4,131
Revolving Credit Facility \| EBITDARM Coverage, 1.0x to 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	9,909
2021 \| Mezzanine
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	25,799
2021 \| Mezzanine \| EBITDARM Coverage above 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	3,566
2021 \| Mezzanine \| EBITDARM Coverage, 1.0x to 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	22,233
2020 [Member] \| Mortgages [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	24,342
2020 [Member] \| Mortgages [Member] \| EBITDARM Coverage Below 1.0x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	3,960
2020 [Member] \| Mortgages [Member] \| EBITDARM Coverage above 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	20,382
2019 \| Mortgages [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	48,136
2019 \| Mortgages [Member] \| EBITDARM Coverage Below 1.0x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	39,123
2019 \| Mortgages [Member] \| EBITDARM Coverage above 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	9,013
2019 \| Mezzanine
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	750
2019 \| Mezzanine \| EBITDARM Coverage Not Available
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	750
2018 \| Mortgages [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	137,306
2018 \| Mortgages [Member] \| EBITDARM Coverage above 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	28,700
2018 \| Mortgages [Member] \| EBITDARM Coverage, 1.0x to 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	108,606
Prior to 2017 \| Mortgages [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	14,402
Prior to 2017 \| Mortgages [Member] \| EBITDARM Coverage Below 1.0x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	10,000
Prior to 2017 \| Mortgages [Member] \| EBITDARM Coverage above 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	4,402
Prior to 2017 \| Mezzanine
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	24,972
Prior to 2017 \| Mezzanine \| EBITDARM Coverage Below 1.0x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	14,500
Prior to 2017 \| Mezzanine \| EBITDARM Coverage, 1.0x to 1.5x
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Gross	$ 10,472

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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