Revenues - Summary of Revenues (Parenthetical) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Operating Leases Lease Income [Abstract]
Variable rental revenue related to tenant reimbursements	$ 17,373

Amount of operating lease income from variable lease payments paid and payable to lessor, excluding amount included in measurement of lease receivable.

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=109225645&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 (c)
-URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919372-209981

Name:	us-gaap_OperatingLeaseVariableLeaseIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration