Real Estate (Rental Income) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Real Estate [Abstract]
Rental income from operating leases	$ 650,112
Rental income from operating leases		$ 602,131	$ 565,405
Earned income from direct financing leases	798
Earned income from direct financing leases		923	978
Percentage rent	1,310
Percentage rent		1,561	1,700
Real estate expense reimbursement from tenants	16,789	16,784	15,512
Rental income	669,009
Rental income		621,399	583,595
Revenue recognized	1,872	309	$ 1,411
Balance of accrued rental income	28,897	25,387
Allowances	$ 1,842	$ 1,842

Deferred Lease Income, Allowances

No definition available.

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- Definition

Operating And Capital Leases, Income Statement, Lease Revenue

+ References

No definition available.

+ Details

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- Definition

Operating Lease Income Statement, Real Estate Expense Reimbursement From Tenants

+ References

No definition available.

+ Details

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- Definition

Revenue realized in the period on direct financing leases.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount, after accumulated amortization, of deferred lease income. Includes, but is not limited to, amount paid in advance by lessee.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15)
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

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- Definition

Amount of lease income from variable lease payments, interest income on direct financing lease and after offset of loss recognized at commencement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=77888421&loc=SL77919311-209978

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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=118952077&loc=SL77927221-108306

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor.

+ References

+ Details

Name:	us-gaap_LeaseIncome
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Balance Type:	credit
Period Type:	duration

- Definition

Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919372-209981

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-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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Balance Type:	credit
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- Definition

The total amount of lease revenue recognized for the period for which the lessee was obligated under leasing arrangements regardless of any other events or conditions. This amount excludes contingent revenue and sublease revenue.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e39896-112707

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- Definition

This element represents the rental revenue earned during the period from lessee-operators based on revenues generated in their operations, generally in excess of a base amount. Such rental revenue is generally stipulated in the lease agreement, usually will provide for a fixed percentage of revenue to be paid as additional (or possibly only) rent due the lessor, and may be based on gross revenues, net revenues, or multiple variations thereof. Percentage rent is often required under leases with retail outlets located on premises owned by hoteliers, cruise lines, others in the hospitality industry, and shopping mall operators, among others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of the adjustment to rental revenues to measure escalating leasing revenues on a straight line basis.

+ References

No definition available.

+ Details

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- Definition

Amount of variable lease payments from operating, direct financing, and sales-type leases, excluding amount included in measurement of lease receivable.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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-Subparagraph (c)
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+ Details

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