Leases - Lease Income (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($) Lease	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) Lease	Sep. 30, 2018 USD ($)
Leases [Abstract]
Ground leases not yet commenced \| Lease	1		1
Rental income \| $	$ 117,740,000	$ 111,452,000	$ 342,787,000	$ 331,247,000

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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

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