Revenue Recognition - Disaggregation of Lease Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Minimum lease payments	$ 33,835	$ 39,059	$ 70,012	$ 78,466
Lease income, net	40,718	55,613	92,002	111,112
Provision for estimated credit losses	(5,995)	(316)	(6,758)	(521)
Tax and insurance recoveries
Disaggregation of Revenue [Line Items]
Lease income, net	6,384	8,717	14,514	16,975
Common area maintenance and other recoveries
Disaggregation of Revenue [Line Items]
Lease income, net	4,652	5,348	9,802	11,125
Amortization of above and below-market leases and lease inducements, net
Disaggregation of Revenue [Line Items]
Lease income, net	1,306	1,327	2,848	2,918
Short-term, termination fee and other lease income
Disaggregation of Revenue [Line Items]
Lease income, net	$ 536	$ 1,478	$ 1,584	$ 2,149

Amount of expense (reversal of expense) for expected credit loss on right to consideration in exchange for good or service transferred to customer when right to consideration is unconditional.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130534-203044

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No definition available.

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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

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=121576215&loc=SL77919372-209981

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Amount of operating lease income from lease payments paid and payable to lessor. Excludes 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 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=121640914&loc=SL77927221-108306

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919372-209981

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