Real Estate - Disposed Properties to Unaffiliated Parties (Parenthetical) (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Net sales proceeds of unconsolidated rental properties	$ 393,439	$ 287,173
Rental Properties - Unconsolidated [Member]
Ownership percentage	20.00%
Net sales proceeds of unconsolidated rental properties	$ 78,300

Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

Name:	us-gaap_ProceedsFromSaleOfRealEstateHeldforinvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration