Investment in Real Estate Partnership - Maximum Exposure to Loss (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Guarantor Obligations [Line Items]
Maximum exposure to loss	$ 66,261
Net carrying value
Guarantor Obligations [Line Items]
Maximum exposure to loss	14,421
OP Unit Purchase Agreement
Guarantor Obligations [Line Items]
Maximum exposure to loss	3,000
Notes payable
Guarantor Obligations [Line Items]
Maximum exposure to loss	$ 48,840

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

Name:	us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant